Extracellular proteins play important roles in, among other things, the formation, differentiation and maintenance of multicellular organisms. The fate of many individual cells, e.g., proliferation, migration, differentiation, or interaction with other cells, is typically governed by information received from other cells and/or the immediate environment. This information is often transmitted by secreted polypeptides (for instance, mitogenic factors, survival factors, cytotoxic factors, differentiation factors, neuropeptides, and hormones) which are, in turn, received and interpreted by diverse cell receptors or membrane-bound proteins. These secreted polypeptides or signaling molecules normally pass through the cellular secretory pathway to reach their site of action in the extracellular environment.
Secreted proteins have various industrial applications, including as pharmaceuticals, diagnostics, biosensors and bioreactors. Most protein drugs available at present, such as thrombolytic agents, interferons, interleukins, erythropoietins, colony stimulating factors, and various other cytokines, are secretory proteins. Their receptors, which are membrane proteins, also have potential as therapeutic or diagnostic agents. Efforts are being undertaken by both industry and academia to identify new, native secreted proteins. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci. 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
Membrane-bound proteins and receptors can play important roles in, among other things, the formation, differentiation and maintenance of multicellular organisms. The fate of many individual cells, e.g., proliferation, migration, differentiation, or interaction with other cells, is typically governed by information received from other cells and/or the immediate environment. This information is often transmitted by secreted polypeptides (for instance, mitogenic factors, survival factors, cytotoxic factors, differentiation factors, neuropeptides, and hormones) which are, in turn, received and interpreted by diverse cell receptors or membrane-bound proteins. Such membrane-bound proteins and cell receptors include, but are not limited to, cytokine receptors, receptor kinases, receptor phosphatases, receptors involved in cell-cell interactions, and cellular adhesin molecules like selectins and integrins. For instance, transduction of signals that regulate cell growth and differentiation is regulated in part by phosphorylation of various cellular proteins. Protein tyrosine kinases, enzymes that catalyze that process, can also act as growth factor receptors. Examples include fibroblast growth factor receptor and nerve growth factor receptor.
Membrane-bound proteins and receptor molecules have various industrial applications, including as pharmaceutical and diagnostic agents. Receptor immunoadhesins, for instance, can be employed as therapeutic agents to block receptor-ligand interactions. The membrane-bound proteins can also be employed for screening of potential peptide or small molecule inhibitors of the relevant receptor/ligand interaction.
Efforts are being undertaken by both industry and academia to identify new, native receptor or membrane-bound proteins. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel receptor or membrane-bound proteins.
1. PRO211 and PRO217
Epidermal growth factor (EGF) is a conventional mitogenic factor that stimulates the proliferation of various types of cells including epithelial cells and fibroblasts. EGF binds to and activates the EGF receptor (EGFR), which initiates intracellular signaling and subsequent effects. The EGFR is expressed in neurons of the cerebral cortex, cerebellum, and hippocampus in addition to other regions of the central nervous system (CNS). In addition, EGF is also expressed in various regions of the CNS. Therefore, EGF acts not only on mitotic cells, but also on postmitotic neurons. In fact, many studies have indicated that EGF has neurotrophic or neuromodulatory effects on various types of neurons in the CNS. For example, EGF acts directly on cultured cerebral cortical and cerebellar neurons, enhancing neurite outgrowth and survival. On the other hand, EGF also acts on other cell types, including septal cholinergic and mesencephalic dopaminergic neurons, indirectly through glial cells. Evidence of the effects of EGF on neurons in the CNS is accumulating, but the mechanisms of action remain essentially unknown. EGF-induced signaling in mitotic cells is better understood than in postmitotic neurons. Studies of cloned pheochromocytoma PC12 cells and cultured cerebral cortical neurons have suggested that the EGF-induced neurotrophic actions are mediated by sustained activation of the EGFR and mitogen-activated protein kinase (MAPK) in response to EGF. The sustained intracellular signaling correlates with the decreased rate of EGFR down-regulation, which might determine the response of neuronal cells to EGF. It is likely that EGF is a multi-potent growth factor that acts upon various types of cells including mitotic cells and postmitotic neurons.
EGF is produced by the salivary and Brunner's glands of the gastrointestinal system, kidney, pancreas, thyroid gland, pituitary gland, and the nervous system, and is found in body fluids such as saliva, blood, cerebrospinal fluid (CSF), urine, amniotic fluid, prostatic fluid, pancreatic juice, and breast milk, Plata-Salaman, Peptides 12: 653-663 (1991).
EGF is mediated by its membrane specific receptor, which contains an intrinsic tyrosine kinase. Stoscheck et al., J. Cell Biochem. 31: 135-152 (1986). EGF is believed to function by binding to the extracellular portion of its receptor which induces a transmembrane signal that activates the intrinsic tyrosine kinase.
Purification and sequence analysis of the EGF-like domain has revealed the presence of six conserved cysteine residues which cross-bind to create three peptide loops, Savage et al., J. Bid. Chem. 248: 7669-7672 (1979). It is now generally known that several other peptides can react with the EGF receptor which share the same generalized motif. Non isolated peptides having this motif include TGF-α, amphiregulin, schwannoma-derived growth factor (SDGF), heparin-binding EGF-like growth factors and certain virally encoded peptides (e.g., Vaccinia virus, Reisner, Nature 313: 801-803 (1985), Shope fibroma virus, Chang et al., Mol Cell Biol. 7: 535-540 (1987), Molluscum contagiosum, Porter and Archard, J. Gen. Virol. 68: 673-682 (1987), and Myxoma virus, Upton et al., J. Virol. 61: 1271-1275 (1987), Prigent and Lemoine, Prog. Growth Factor Res. 4: 1-24 (1992).
EGF-like domains are not confined to growth factors but have been observed in a variety of cell-surface and extracellular proteins which have interesting properties in cell adhesion, protein-protein interaction and development, Laurence and Gusterson, Tumor Biol. 11: 229-261 (1990). These proteins include blood coagulation factors (factors VI, IX, X, XII, protein C, protein S, protein Z, tissue plasminogen activator, urokinase), extracellular matrix components (laminin, cytotactin, entactin), cell surface receptors (LDL receptor, thrombomodulin receptor) and immunity-related proteins (complement C1r, uromodulin).
Even more interesting, the general structure pattern of EGF-like precursors is preserved through lower organisms as well as in mammalian cells. A number of genes with developmental significance have been identified in invertebrates with EGF-like repeats. For example, the notch gene of Drosophila encodes 36 tandemly arranged 40 amino acid repeats which show homology to EGF, Wharton et al., Cell 43: 557-581 (1985). Hydropathy plots indicate aputative membrane spanning domain, with the EGF-related sequences being located on the extracellular side of the membrane. Other homeotic genes with EGF-like repeats include Delta, 95F and 5ZD which were identified using probes based on Notch, and the nematode gene Lin-12 which encodes a putative receptor for a developmental signal transmitted between two specified cells.
Specifically, EGF has been shown to have potential in the preservation and maintenance of gastrointestinal mucosa and the repair of acute and chronic mucosal lesions, Konturek et al., Eur. J. Gastroenterol Hepatol. 7 (10), 933-37 (1995), including the treatment of necrotizing enterocolitis, Zollinger-Ellison syndrome, gastrointestinal ulceration gastrointestinal ulcerations and congenital microvillus atrophy, Guglietta and Sullivan, Eur. J. Gastroenterol Hepatol, 7(10), 945-50 (1995). Additionally, EGF has been implicated in hair follicle differentiation; du Cros, J. Invest. Dermatol. 101 (1 Suppl.), 106S-113S (1993), Hillier, Clin. Endocrinol. 33(4), 427-28 (1990); kidney function, Hamm et al., Semin. Nephrol. 13 (1): 109-15 (1993), Harris, Am. J. Kidney Dis. 17(6): 627-30 (1991); tear fluid, van Setten et al., Int. Ophthalmol 15(6); 359-62 (1991); vitamin K mediated blood coagulation, Stenflo et al., Blood 78(7): 1637-51 (1991). EGF is also implicated various skin disease characterized by abnormal keratinocyte differentiation, e.g., psoriasis, epithelial cancers such as squamous cell carcinomas of the lung, epidermoid carcinoma of the vulva and gliomas. King et al., Am. J. Med. Sci. 296: 154-158 (1988).
Of great interest is mounting evidence that genetic alterations in growth factors signaling pathways are closely linked to developmental abnormalities and to chronic diseases including cancer. Aaronson, Science 254: 1146-1153 (1991). For example, c-erb-2 (also known as HER-2), a proto-oncogene with close structural similarity to EGF receptor protein, is overexpressed in human breast cancer. King et al., Science 229: 974-976 (1985); Gullick, Hormones and their actions, Cooke et al., eds, Amsterdam, Elsevier, pp 349-360 (1986).
We herein describe the identification and characterization of novel polypeptides having homology to EGF, wherein those polypeptides are herein designated PRO211 and PRO217.
2. PRO230
Nepbritis is a condition characterized by inflammation of the kidney affecting the structure and normal function of the kidney. This condition can be chronic or acute and is generally caused by infection, degenerative process or vascular disease. In all cases, early detection is desirable so that the patient with nephritis can begin treatment of the condition.
An approach to detecting nephritis is to determine the antigens associated with nephritis and antibodies thereto. In rabbit, a tubulointerstitial nephritis antigen (TIN-ag) has been reported in Nelson, T. R., et al., J. Biol. Chem., 270(27):16265-70 (July 1995) (GENBANK/U24270). This study reports that the rabbit TIN-ag is a basement membrane glycoprotein having a predicted amino acid sequence which has a carboxyl-terminal region exhibiting 30% homology with human preprocathepsin B, a member of the cystein proteinase family of proteins. It is also reported that the rabbit TIN-ag has a domain in the amino-terminal region containing an epidermal growth factor-ike motif that shares homology with laminin A and S chains, alpha 1 chain of type I collagen, von Willebrand's factor and mucin, indicating structural and functional similarities. Studies have also been conducted in mice. However, it is desirable to identify tubulointerstitial nephritis antigens in humans to aid in the development of early detection methods and treatment of nephritis.
Proteins which have homology to tubulointerstitial nephritis antigens are of particular interest to the medical and industrial communities. Often, proteins having homology to each other have similar function. It is also of interest when proteins having homology do not have similar functions, indicating that certain structural motifs identify information other than function, such as locality of function. We herein describe the identification and characterization of a novel polypeptide, designated hgerein as PRO230, which has homology to tubulointerstitial nephritis antigens.
3. PRO232
Stem cells are undifferentiated cells capable of (a) proliferation, (b) self maintenance, (c) the production of a large number of differentiated functional progeny, (d) regeneration of tissue after injury and/or (e) a flexibility in the use of these options. Stem cells often express cell surface antigens which are capable of serving as cell specific markers that can be exploited to identify stem cells, thereby providing a means for identifying and isolating specific stem cell populations.
Having possession of different stem cell populations will allow for a number of important applications. For example, possessing a specific stem cell population will allow for the identification of growth factors and other proteins which are involved in their proliferation and differentiation. In addition, there may be as yet undiscovered proteins which are associated with (1) the early steps of dedication of the stem cell to a particular lineage, (2) prevention of such dedication, and (3) negative control of stem cell proliferation, all of which may be identified if one has possession of the stem cell population. Moreover, stem cells are important and ideal targets for gene therapy where the inserted genes promote the health of the individual into whom the stem cells are transplanted. Finally, stem cells may play important roles in transplantation of organs or tissues, for example liver regeneration and skin grafting.
Given the importance of stem cells in various different applications, efforts are currently being undertaken by both industry and academia to identify new, native stem cell antigen proteins so as to provide specific cell surface markers for identifying stem cell populations as well as for providing insight into the functional roles played by stem cell antigens in cell proliferation and differentiation. We herein describe the identification and characterization of novel polypeptides having homology to a stem cell antigen, wherein those polypeptides are herein designated as PRO232 polypeptides.
4. PRO187
Growth factors are molecular signals or mediators that enhance cell growth or proliferation, alone or in concert, by binding to specific cell surface receptors. However, there are other cellular reactions than only growth upon expression to growth factors. As a result, growth factors are better characterized as multifunctional and potent cellular regulators. Their biological effects include proliferation, chemotaxis and stimulation of extracellular matrix production. Growth factors can have both stimulatory and inhibitory effects. For example, transforming growth factor (TGF-β) is highly pleiotropic and can stimulate proliferation in some cells, especially connective tissue, while being a potent inhibitor of proliferation in others, such as lymphocytes and epithelial cells.
The physiological effect of growth stimulation or inhibition by growth factors depends upon the state of development and differentiation of the target tissue. The mechanism of local cellular regulation by classical endocrine molecules involves comprehends autocrine (same cell), juxtacrine (neighbor cell), and paracrine (adjacent cells) pathways. Peptide growth factors are elements of a complex biological language, providing the basis for intercellular communication. They permit cells to convey information between each other, mediate interaction between cells and change gene expression. The effect of these multifunctional and pluripotent factors is dependent on the presence or absence of other peptides.
FGF-8 is a member of the fibroblast growth factors (FGFs) which are a family of heparin-binding, potent mitogens for both normal diploid fibroblasts and established cell lines, Gospodarowicz et al. (1984), Proc. Natl. Acad. Sci. USA 81:6963. The FGF family comprises acidic FGF (FGF-1), basic FGF (FGF-2), INT-2 (FGF-3), K-FGF/HST (FGF-4), FGF-5, FGF-6, KGF (FGF-7), AIGF (FGF-8) among others. All FGFs have two conserved cysteine residues and share 30-50% sequence homology at the amino acid level. These factors are mitogenic for a wide variety of normal diploid mesoderm-derived and neural crest-derived cells, including granulosa cells, adrenal cortical cells, chondrocytes, myoblasts, corneal and vascular endothelial cells (bovine or human), vascular smooth muscle cells, lens, retina and prostatic epithelial cells, oligodendrocytes, astrocytes, chrondocytes, myoblasts and osteoblasts.
Fibroblast growth factors can also stimulate a large number of cell types in a non-mitogenic manner. These activities include promotion of cell migration into wound area (chemotaxis), initiation of new blood vessel formulation (angiogenesis), modulation of nerve regeneration and survival (neurotrophism), modulation of endocrine functions, and stimulation or suppression of specific cellular protein expression, extracellular matrix production and cell survival. Baird & Bohlen, Handbook of Exp. Pharmacol. 95(1): 369-418, Springer, (1990). These properties provide a basis for using fibroblast growth factors in therapeutic approaches to accelerate wound healing, nerve repair, collateral blood vessel formation, and the like. For example, fibroblast growth factors have been suggested to minimize myocardium damage in heart disease and surgery (U.S. Pat. No. 4,378,347).
FGF-8, also known as androgen-induced growth factor (AIGF), is a 215 amino acid protein which shares 30-40% sequence homology with the other members of the FGF family. FGF-8 has been proposed to be under androgenic regulation and induction in the mouse mammary carcinoma cell line SC3. Tanaka et al., Proc. Natl. Acad. Sci. USA 89: 8928-8932 (1992); Sato et al., J. Steroid Biochem. Molec. Biol. 47: 91-98 (1993). As a result, FGF-8 may have a local role in the prostate, which is known to be an androgen-responsive organ. FGF-8 can also be oncogenic, as it displays transforming activity when transfected into NIH-3T3 fibroblasts. Kouhara et al., Oncogene 9 455-462 (1994). While FGF-8 has been detected in heart, brain, lung, kidney, testis, prostate and ovary, expression was also detected in the absence of exogenous androgens. Schmitt et al., J. Steroid Biochem. Mol. Biol. 57 (3-4): 173-78 (1996).
FGF-8 shares the property with several other FGFs of being expressed at a variety of stages of murine embryogenesis, which supports the theory that the various FGFs have multiple and perhaps coordinated roles in differentiation and embryogenesis. Moreover, FGF-8 has also been identified as a protooncogene that cooperates with Wnt-1 in the process of mammary tumorigenesis (Shackleford et al., Proc. Natl. Acad. Sci. USA 90, 740-744 (1993); Heikinheimo et al., Mech. Dev. 48: 129-138 (1994)).
In contrast to the other FGFs, FGF-8 exists as three protein isoforms, as a result of alternative splicing of the primary transcript. Tanaka et al., supra. Normal adult expression of FGF-8 is weak and confined to gonadal tissue, however northern blot analysis has indicated that FGF-8 mRNA is present from day 10 through day 12 or murine gestation, which suggests that FGF-8 is important to normal development. Heikinheimo et al., Mech Dev. 48(2): 129-38 (1994). Further in situ hybridization assays between day 8 and 16 of gestation indicated initial expression in the surface ectoderm of the first bronchial arches, the frontonasal process, the forebrain and the midbrain-hindbrain junction. At days 10-12, FGF-8 was expressed in the surface ectoderm of the forelimb and hindlimb buds, the nasal its and nasopharynx, the infundibulum and in the telencephalon, diencephalon and metencephalon. Expression continues in the developing hindlimbs through day 13 of gestation, but is undetectable thereafter. The results suggest that FGF-8 has a unique temporal and spatial pattern in embryogenesis and suggests a role for this growth factor in multiple regions of ectodermal differentiation in the post-gastrulation embryo.
We herein describe the identification of novel poypeptides having homology to FGF-8, wherein those polypeptides are heein designated PRO187 polypeptides.
5. PRO265
Protein-protein interactions include receptor and antigen complexes and signaling mechanisms. As more is known about the structural and functional mechanisms underlying protein-protein interactions, protein-protein interactions can be more easily manipulated to regulate the particular result of the protein-protein interaction. Thus, the underlying mechanisms of protein-protein interactions are of interest to the scientific and medical community.
All proteins containing leucine-rich repeats are thought to be involved in protein-protein interactions. Leucine-rich repeats are short sequence motifs present in a number of proteins with diverse functions and cellular locations. The crystal structure of ribonuclease inhibitor protein has revealed that leucine-rich repeats correspond to beta-alpha structural units. These units are arranged so that they form a parallel beta-sheet with one surface exposed to solvent, so that the protein acquires an unusual, nonglubular shape. These two features have been indicated as responsible for the protein-binding functions of proteins containing leucine-rich repeats. See, Kobe and Deisenhofer, Trends Biochem. Sci., 19(10):415-421 (October 1994).
A study has been reported on leucine-rich proteoglycans which serve as tissue organizers, orienting and ordering collagen fibrils during ontogeny and are involved in pathological processes such as wound healing, tissue repair, and tumor stroma formation. Iozzo, R. V., Crit. Rev. Biochem. Mol. Biol., 32(2):141-174 (1997). Others studies implicating leucine rich proteins in wound healing and tissue repair are De La Salle, C., et al., Vouv. Rev. Fr. Hematol. (Germany), 37(4):215-222 (1995), reporting mutations in the leucine rich motif in a complex associated with the bleeding disorder Bernard-Soulier syndrome and Chlemetson, K. J., Thromb. Haemost. (Germany), 74(1): 111-116 (July 1995), reporting that platelets have leucine rich repeats. Another protein of particular interest which has been reported to have leucine-rich repeats is the SLIT protein which has been reported to be useful in treating neuro-degenerative diseases such as Alzheimer's disease, nerve damage such as in Parkinson's disease, and for diagnosis of cancer, see, Artavanistsakonas, S. and Rothberg, J. M., WO9210518-A1 by Yale University. Other studies reporting on the biological functions of proteins having leucine-rich repeats include: Tayar, N., et al., Mol. Cell Endocrinol., (Ireland), 125(1-2):65-70 (December 1996) (gonadotropin receptor involvement); Miura, Y., et al., Nippon Rinsho (Japan), 54(7):1784-1789 (July 1996) (apoptosis involvement); Harris, P. C., et al., J. Am. Soc. Nephrol., 6(4):1125-1133 (October 1995) (kidney disease involvement); and Ruoslahti, E. I., et al., WO9110727-A by La Jolla Cancer Research Foundation (decorin binding to transforming growth factor-β involvement for treatment for cancer, wound healing and scarring). Also of particular interest is fibromodulin and its use to prevent or reduce dermal scarring. A study of fibromodulin is found in U.S. Pat. No. 5,654,270 to Ruoslahti, et al.
Efforts are therefore being undertaken by both industry and academia to identify new proteins having leucine rich repeats to better understand protein-protein interactions. Of particular interest are those proteins having leucine rich repeats and homology to known proteins having leucine rich repeats such as fibromodulin, the SLIT protein and platelet glycoprotein V. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound proteins having leucine rich repeats. We herein describe the identification and characterization of novel polypeptides having homology to fibromodulin, herein designated as PRO265 polypeptides.
6. PRO219
Human matrilin-2 polypeptide is a member of the von Willebrand factor type A-like module superfamily. von Willebrand factor is a protein which plays an important role in the maintenence of hemostasis. More specifically, von Willebrand factor is a protein which is known to participate in platelet-vessel wall interactions at the site of vascular injury via its ability to interact and form a complex with Factor VIII. The absence of von Willebrand factor in the blood causes an abnormality with the blood platelets that prevents platelet adhesion to the vascular wall at the site of the vascular injury. The result is the propensity for brusing, nose bleeds, intestinal bleeding, and the like comprising von Willebrand's disease.
Given the physiological importance of the blood clotting factors, efforts are currently being undertaken by both industry and academia to identify new, native proteins which may be involved in the coagulation process. We herein describe the identification of a novel full-length polypeptide which possesses homology to the human matrilin-2 precursor polypeptide.
7. PRO246
The cell surface protein HCAR is a membrane-bound protein that acts as a receptor for subgroup C of the adenoviruses and subgroup B of the coxsackieviruses. Thus, HCAR may provide a means for mediating viral infection of cells in that the presence of the HCAR receptor on the cellular surface provides a binding site for viral particles, thereby facilitating viral infection.
In light of the physiological importance of membrane-bound proteins and specficially those which serve a cell surface receptor for viruses, efforts are currently being undertaken by both industry and academia to identify new, native membrane-bound receptor proteins. Many of these efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel receptor proteins. We herein describe a novel membrane-bound polypeptide (designated herein as PRO246) having homology to the cell surface protein HCAR and to various tumor antigens including A33 and carcinoembryonic antigen, wherein this polypeptide may be a novel cell surface virus receptor or tumor antigen.
8. PRO228
There are a number of known seven transmembrane proteins and within this family is a group which includes CD97 and EMR1. CD97 is a seven-span transmembrane receptor which has a cellular ligand, CD55, DAF. Hamann, et al., J. Exp. Med. (U.S.), 184(3):1189 (1996). Additionally, CD97 has been reported as being a dedifferentiation marker in human thyroid carcinomas and as associated with inflammation. Aust, et al., Cancer Res. (U.S.), 57(9):1798 (1997); Gray, et al., J. Immunol. (U.S.), 157(12):5438 (1996). CD97 has also been reported as being related to the secretin receptor superfamily, but unlike known members of that family, CD97 and EMR1 have extended extracellular regions that possess several EGF domains at the N-terminus. Hamann, et al., Genomics, 32(1):144 (1996); Harmann, et al., J. Immunol., 155(4):1942 (1995). EMR1 is further described in Lin, et al., Genomics, 41(3):301 (1997) and Baud, et al., Genomics, 26(2):334 (1995). While CD97 and EMR1 appear to be related to the secretin receptors, a known member of the secretin family of G protein-coupled receptors includes the alpha-latroxin receptor, latrophilin, which has been described as calcium independent and abundant among neuronal tissues. Lelianova, et al., J. Biol. Chem., 272(34), 21504 (1997); Davletov, et al., J. Biol. Chem. (U.S.), 271(38):23239 (1996). Both members of the secretin receptor superfamily and non-members which are related to the secretin receptor superfamily, or CRF and calcitonin receptors are of interest. In particular, new members of these families, identified by their homology to known proteins, are of interest.
Efforts are being undertaken by both industry and academia to identify new membrane-bound receptor proteins, particularly transmembrane proteins with EGF repeats and large N-terminuses which may belong to the family of seven-transmembrane proteins of which CD97 and EMR1 are members. We herein describe the identification and charactization of novel polypeptides having homology to CD97 and EMR1, designated herein as PRO228 polypeptides.
9. PRO533
Growth factors are molecular signals or mediators that enhance cell growth or proliferation, alone or in concert, by binding to specific cell surface receptors. However, there are other cellular reactions than only growth upon expression to growth factors. As a result, growth factors are better characterized as multifunctional and potent cellular regulators. Their biological effects include proliferation, chemotaxis and stimulation of extracellular matrix production. Growth factors can have both stimulatory and inhibitory effects. For example, transforming growth factors (TGF-β) is highly pleiotropic and can stimulate proliferation in some cells, especially connective tissues, while being a potent inhibitor of proliferation in others, such as lymphocytes and epithelial cells.
The physiological effect of growth stimulation or inhibition by growth factors depends upon the state of development and differentiation of the target tissue. The mechanism of local cellular regulation by classical endocrine molecules comprehends autocrine (same cell), juxtacrine (neighbor cell), and paracrine (adjacent cell) pathways. Peptide growth factors are elements of a complex biological language, providing the basis for intercellular communication. They permit cells to convey information between each other, mediate interaction between cells and change gene expression. The effect of these multifunctional and pluripotent factors is dependent on the presence or absence of other peptides.
Fibroblast growth factors (FGFs) are a family of heparin-binding, potent mitogens for both normal diploid fibroblasts and established cell lines, Godpodarowicz, D. et al. (1984), Proc. Natl. Acad. Sci. USA 81: 6983, the FGF family comprises acidic FGF (FGF-1), basic FGF (FGF-2), INT-2 (FGF-3), K-FGF/HST (FGF-4), FGF-5, FGF-6, KGF (FGF-7), AIGF (FGF-8) among others. All FGFs have two conserved cysteine residues and share 30-50% sequence homology at the amino acid level. These factors are mitogenic for a wide variety of normal diploid mesoderm-derived and neural crest-derived cells, inducing granulosa cells, adrenal cortical cells, chrondocytes, myoblasts, corneal and vascular endothelial cells (bovine or human), vascular smooth muscle cells, lens, retina and prostatic epithelial cells, oligodendrocytes, astrocytes, chrondocytes, myoblasis and osteoblasts.
Fibroblast growth factors can also stimulate a large number of cell types in a non-mitogenic manner. These activities include promotion of cell migration into a wound area (chemotaxis), initiation of new blood vessel formulation (angiogenesis), modulation of nerve regeneration and survival (neurotrophism), modulation of endocrine functions, and stimulation or suppression of specific cellular protein expression, extracellular matrix production and cell survival. Baird, A. & Bohlen, P., Handbook of Exp. Phrmacol. 95(1): 369-418 (1990). These properties provide a basis for using fibroblast growth factors in therapeutic approaches to accelerate wound healing, nerve repair, collateral blood vessel formation, and the like. For example, fibroblast growth factors, have been suggested to minimize myocardium damage in heart disease and surgery (U.S. Pat. No. 4,378,437).
We herein describe the identification and characterization of novel polypeptides having homology to FGF, herein designated PRO533 polypeptides.
10. PRO245
Some of the most important proteins involved in the above described regulation and modulation of cellular processes are the enzymes which regulate levels of protein phosphorylation in the cell. For example, it is known that the transduction of signals that regulate cell growth and differentiation is regulated at least in part by phosphorylation and dephosphorylation of various cellular proteins. The enzymes that catalyze these processes include the protein kinases, which function to phosphorylate various cellular proteins, and the protein phosphatases, which function to remove phosphate residues from various cellular proteins. The balance of the level of protein phosphorylation in the cell is thus mediated by the relative activities of these two types of enzymes.
Although many protein kinase enzymes have been identified, the physiological role played by many of these catalytic proteins has yet to be elucidated. It is well known, however, that a number of the known protein kinases function to phosphorylate tyrosine residues in proteins, thereby leading to a variety of different effects. Perhaps most importantly, there has been a great deal of interest in the protein tyrosine kinases since the discovery that many oncogene products and growth factors possess intrinsic protein tyrosine kinase activity. There is, therefore, a desire to identify new members of the protein tyrosine kinase family.
Given the physiological importance of the protein kinases, efforts are being undertaken by both industry and academia to identify new, native kinase proteins. Many of these efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel kinase proteins. We herein describe the identification and characterization of novel polypeptides having homology to tyrosine kinase proteins, designated herein as PRO245 polypeptides.
11. PRO220, PRO221 and PRO227
Protein-protein interactions include receptor and antigen complexes and signaling mechanisms. As more is known about the structural and functional mechanisms underlying protein-protein interactions, protein-protein interactions can be more easily manipulated to regulate the particular result of the protein-protein interaction. Thus, the underlying mechanisms of protein-protein interactions are of interest to the scientific and medical community.
All proteins containing leucine-rich repeats are thought to be involved in protein-protein interactions. Leucine-rich repeats are short sequence motifs present in a number of proteins with diverse functions and cellular locations. The crystal structure of ribonuclease inhibitor protein has revealed that leucine-rich repeats correspond to beta-alpha structural units. These units are arranged so that they form a parallel beta-sheet with one surface exposed to solvent, so that the protein acquires an unusual, nonglubular shape. These two features have been indicated as responsible for the protein-binding functions of proteins containing leucine-rich repeats. See, Kobe and Deisenhofer, Trends Biochem. Sci., 19(10):415-421 (October 1994).
A study has been reported on leucine-rich proteoglycans which serve as tissue organizers, orienting and ordering collagen fibrils during ontogeny and are involved in pathological processes such as wound healing, tissue repair, and tumor stroma formation. Iozzo, R. V., Crit. Rev. Biochem. Mol. Biol., 32(2):141-174 (1997). Others studies implicating leucine rich proteins in wound healing and tissue repair are De La Salle, C., et al., Vouv. Rev. Fr. Hematol. (Germany), 37(4):215-222 (1995), reporting mutations in the leucine rich motif in a complex associated with the bleeding disorder Bernard-Soulier syndrome and Chlemetson, K. J., Thromb. Haemost. (Germany), 74(1):111-116 (July 1995), reporting that platelets have leucine rich repeats. Another protein of particular interest which has been reported to have leucine-rich repeats is the SLIT protein which has been reported to be useful in treating neuro-degenerative diseases such as Alzheimer's disease, nerve damage such as in Parkinson's disease, and for diagnosis of cancer, see, Artavanistsakonas, S. and Rothberg, J. M., WO9210518-A1 by Yale University. Other studies reporting on the biological functions of proteins having leucine-rich repeats include: Tayar, N., et al., Mol. Cell Endocrinol., (Ireland), 125(1-2):65-70 (December 1996) (gonadotropin receptor involvement); Miura, Y., et al., Nippon Rinsho (Japan), 54(7): 1784-1789 (July 1996) (apoptosis involvement); Harris, P. C., et al., J. Am. Soc. Nephrol., 6(4):1125-1133 (October 1995) (kidney disease involvement); and Ruoslahti, E. I., et al., WO9110727-A by La Jolla Cancer Research Foundation (decorin binding to transforming growth factors involvement for treatment for cancer, wound healing and scarring).
Efforts are therefore being undertaken by both industry and academia to identify new proteins having leucine rich repeats to better understand protein-protein interactions. Of particular interest are those proteins having leucine rich repeats and homology to known proteins having leucine rich repeats such as the SLIT protein and platelet glycoprotein V.
12. PRO258
Immunoglobulins are antibody molecules, the proteins that function both as receptors for antigen on the B-cell membrane and as the secreted products of the plasma cell. Like all antibody molecules, immunoglobulins perform two major functions: they bind specifically to an antigen and they participate in a limited number of biological effector functions. Therefore, new members of the Ig superfamily are always of interest. Molecules which act as receptors by various viruses and those which act to regulate immune function are of particular interest. Also of particular interest are those molecules which have homology to known Ig family members which act as virus receptors or regulate immune function. Thus, molecules having homology to poliovirus receptors, CRTAM and CD166 (a ligand for lymphocyte antigen CD6) are of particular interest.
Extracellular and membrane-bound proteins play important roles in the formation, differentiation and maintenance of multicellular organisms. The fate of many individual cells, e.g., proliferation, migration, differentiation, or interaction with other cells, is typically governed by information received from other cells and/or the immediate environment. This information is often transmitted by secreted polypeptides (for instance, mitogenic factors, survival factors, cytotoxic factors, differentiation factors, neuropeptides, and hormones) which are, in turn, received and interpreted by diverse cell receptors or membrane-bound proteins. These secreted polypeptides or signaling molecules normally pass through the cellular secretory pathway to reach their site of action in the extracellular environment, usually at a membrane-bound receptor protein.
We herein describe the identification and characterization of novel polypeptides having homology to CRTAM, designated herein as PRO258 polypeptides.
13. PRO266
Protein-protein interactions include receptor and antigen complexes and signaling mechanisms. As more is known about the structural and functional mechanisms underlying protein-protein interactions, protein-protein interactions can be more easily manipulated to regulate the particular result of the protein-protein interaction. Thus, the underlying mechanisms of protein-protein interactions are of interest to the scientific and medical community.
All proteins containing leucine-rich repeats are thought to be involved in protein-protein interactions. Leucine-rich repeats are short sequence motifs present in a number of proteins with diverse functions and cellular locations. The crystal structure of ribonuclease inhibitor protein has revealed that leucine-rich repeats correspond to beta-alpha structural units. These units are arranged so that they form a parallel beta-sheet with one surface exposed to solvent, so that the protein acquires an unusual, nonglobular shape. These two features have been indicated as responsible for the protein-binding functions of proteins containing leucine-rich repeats. See, Kobe and Deisenhofer, Trends Biochem. Sci., 19(10):415-421 (October 1994).
A study has been reported on leucine-rich proteoglycans which serve as tissue organizers, orienting and ordering collagen fibrils during ontogeny and are involved in pathological processes such as wound healing, tissue repair, and tumor stroma formation. Iozzo, R. V., Crit. Rev. Biochem. Mol. Biol., 32(2):141-174 (1997). Others studies implicating leucine rich proteins in wound healing and tissue repair are De La Salle, C., et al., Vouv. Rev. Fr. Hematol. (Germany), 37(4):215-222 (1995), reporting mutations in the leucine rich motif in a complex associated with the bleeding disorder Bernard-Soulier syndrome and Chlemetson, K. J., Thromb. Haemost. (Germany), 74(1):111-116 (July 1995), reporting that platelets have leucine rich repeats. Another protein of particular interest which has been reported to have leucine-rich repeats is the SLIT protein which has been reported to be useful in treating neuro-degenerative diseases such as Alzheimer's disease, nerve damage such as in Parkinson's disease, and for diagnosis of cancer, see, Artavanistsakonas, S. and Rothberg, J. M., WO9210518-A1 by Yale University. Other studies reporting on the biological functions of proteins having leucine-rich repeats include: Tayar, N., et al., Mol. Cell Endocrinol., (Ireland), 125(1-2):65-70 (December 1996) (gonadotropin receptor involvement); Miura, Y., et al., Nippon Rinsho (Japan), 54(7): 1784-1789 (July 1996) (apoptosis involvement); Harris, P. C., et al., J. Am. Soc. Nephrol., 6(4):1125-1133 (October 1995) (kidney disease involvement); and Ruoslahti, E. I., et al., WO9110727-A by La Jolla Cancer Research Foundation (decorin binding to transforming growth factors involvement for treatment for cancer, wound healing and scarring).
Efforts are therefore being undertaken by both industry and academia to identify new proteins having leucine rich repeats to better understand protein-protein interactions, neuronal development and adhesin molecules. Of particular interest are those proteins having leucine rich repeats and homology to known proteins having leucine rich repeats such as the SLIT protein. We herein describe novel polypeptides having homology to SLIT, designated herein as PRO266 polypeptides.
14. PRO269
Thrombomodulin binds to and regulates the activity of thrombin. It is important in the control of blood coagulation. Thrombomodulin functions as a natural anticoagulant by accelerating the activation of protein C by thrombin. Soluble thrombomodulin may have therapeutic use as an antithrombotic agent with reduced risk for hemorrhage as compared with heparin. Thrombomodulin is a cell surface trans-membrane glycoprotein, present on endothelial cells and platelets. A smaller, functionally active form of thrombomodulin circulates in the plasma and is also found in urine. (In Haeberli, A., Human Protein Data, VCH Oub., N.Y., 1992). Peptides having homology to thrombomodulin are particularly desirable.
We herein describe the identification and characterization of novel polypeptides having homology to thrombomodulin, designated herein as PRO269 polypeptides.
15. PRO287
Procollagen C-proteinase enhancer protein binds to and enhances the activity of bone morphogenic protein “BMP1”/procollagen C-proteinase (PCP). It plays a role in extracellular matrix deposition. BMP1 proteins may be used to induce bone and/or cartilage formation and in wound healing and tissue repair. Therefore, procollagen C-proteinase enhancer protein, BMP1 and proteins having homology thereto, are of interest to the scientific and medical communities.
We herein describe the identification and characterization of novel polypeptides having homology to procollagen C-proteinase enhancer protein precursor and procollagen C-proteinase enhancer protein, designated herein as PRO287 polypeptides.
16. PRO214
Growth factors are molecular signals or mediators that enhances cell growth or proliferation, alone or in concert, by binding to specific cell surface receptors. However, there are other cellular reactions than only growth upon expression to growth factors. As a result, growth factors are better characterized as multifunctional and potent cellular regulators. Their biological effects include proliferation, chemotaxis and stimulation of extracellular matrix production. Growth factors can have both stimulatory and inhibitory effects. For example, transforming growth factor β (TGF-β) is highly pleiotropic and can stimulate proliferation in some cells, especially connective tissue, while being a potent inhibitor of proliferation in others, such as lymphocytes and epithelial cells.
The physiological effect of growth stimulation or inhibition by growth factors depends upon the state of development and differentiation of the target tissue. The mechanism of local cellular regulation by classical endocrine molecules involves comprehends autocrine (same cell), juxtacrine (neighbor cell), and paracrine (adjacent cells) pathways. Peptide growth factors are elements of a complex biological language, providing the basis for intercellular communication. They permit cells to convey information between each other, mediate interaction between cells and change gene expression. The effect of these multifunctional and pluripotent factors is dependent on the presence or absence of other peptides.
Epidermal growth factor (EGF) is a conventional mitogenic factor that stimulates the proliferation of various types of cells including epithelial cells and fibroblasts. EGF binds to and activates the EGF receptor (EGFR), which initiates intracellular signaling and subsequent effects. The EGFR is expressed in neurons of the cerebral cortex, cerebellum, and hippocampus in addition to other regions of the central nervous system (CNS). In addition, EGF is also expressed in various regions of the CNS. Therefore, EGF acts not only on mitotic cells, but also on postnitotic neurons. In fact, many studies have indicated that EGF has neurotrophic or neuromodulatory effects on various types of neurons in the CNS. For example, EGF acts directly on cultured cerebral cortical and cerebellar neurons, enhancing neurite outgrowth and survival. On the other hand, EGF also acts on other cell types, including septal cholinergic and mesencephalic dopaminergic neurons, indirectly through glial cells. Evidence of the effects of EGF on neurons in the CNS is accumulating, but the mechanisms of action remain essentially unknown. EGF-induced signaling in mitotic cells is better understood than in postmitotic neurons. Studies of cloned pheochromocytoma PC12 cells and cultured cerebral cortical neurons have suggested that the EGF-induced neurotrophic actions are mediated by sustained activation of the EGFR and mitogen-activated protein kinase (MAPK) in response to EGF. The sustained intracellular signaling correlates with the decreased rate of EGFR down-regulation, which might determine the response of neuronal cells to EGF. It is likely that EGF is a multi-potent growth factor that acts upon various types of cells including mitotic cells and postmitotic neurons.
EGF is produced by the salivary and Brunner's glands of the gastrointestinal system, kidney, pancreas, thyroid gland, pituitary gland, and the nervous system, and is found in body fluids such as saliva, blood, cerebrospinal fluid (CSF), urine, amniotic fluid, prostatic fluid, pancreatic juice, and breast milk, Plata-Salaman, C R Peptides 12: 653-663 (1991).
EGF is mediated by its membrane specific receptor, which contains an intrinsic tyrosine kinase. Stoscheck C M et al., J. Cell Biochem. 31: 135-152 (1986). EGF is believed to function by binding to the extracellular portion of its receptor which induces a transmembrane signal that activates the intrinsic tyrosine kinase.
Purification and sequence analysis of the EGF-like domain has revealed the presence of six conserved cysteine residues which cross-bind to create three peptide loops, Savage C R et al., J. Biol. Chem. 248: 7669-7672 (1979). It is now generally known that several other peptides can react with the EGF receptor which share the same generalized motif XnCX7CX4/5CX10CXCX5GX2CXn, where X represents any non-cysteine amino acid, and n is a variable repeat number. Non isolated peptides having this motif include TGF-α, amphiregulin, schwannoma-derived growth factor (SDGF), heparin-binding EGF-like growth factors and certain virally encoded peptides (e.g., Vaccinia virus, Reisner A H, Nature 313: 801-803 (1985), Shope fibroma virus, Chang W., et al., Mol Cell Biol. 7: 535-540 (1987), Molluscum contagiosum, Porter C D & Archard L C, J. Gen. Virol. 68: 673-682 (1987), and Myxoma virus, Upton C et al., J. Virol. 61: 1271-1275 (1987). Prigent SA & Lemoine N. R., Prog. Growth Factor Res. 4: 1-24 (1992).
EGF-like domains are not confined to growth factors but have been observed in a variety of cell-surface and extracellular proteins which have interesting properties in cell adhesion, protein-protein interaction and development, Laurence D J R & Gusterson B A, Tumor Biol. 11: 229-261 (1990). These proteins include blood coagulation factors (factors VI, IX, X, XII, protein C, protein S, protein Z, tissue plasminogen activator, urokinase), extracellular matrix components (laminin, cytotactin, entactin), cell surface receptors (LDL receptor, thrombomodulin receptor) and immunity-related proteins (complement C1r, uromodulin).
Even more interesting, the general structure pattern of EGF-like precursors is preserved through lower organisms as well as in mammalian cells. A number of genes with developmental significance have been identified in invertebrates with EGF-like repeats. For example, the notch gene of Drosophila encodes 36 tandemly arranged 40 amino acid repeats which show homology to EGF, Wharton W et al., Cell 43: 557-581 (1985). Hydropathy plots indicate a putative membrane spanning domain, with the EGF-related sequences being located on the extracellular side of the membrane. Other homeotic genes with EGF-like repeats include Delta, 95F and 5ZD which were identified using probes based on Notch, and the nematode gene Lin-12 which encodes a putative receptor for a developmental signal transmitted between two specified cells.
Specifically, EGF has been shown to have potential in the preservation and maintenance of gastrointestinal mucosa and the repair of acute and chronic mucosal lesions, Konturek, P C et al., Eur. J. Gastroenterol Hepatol. 7 (10), 933-37 (1995), including the treatment of necrotizing enterocolitis, Zollinger-Ellison syndrome, gastrointestinal ulceration gastrointestinal ulcerations and congenital microvillus atrophy, A. Guglietta & P B Sullivan, Eur. J. Gastroenterol Hepatol, 7(10), 945-50 (1995). Additionally, EGF has been implicated in hair follicle differentiation; C. L. du Cros, J. Invest. Dermatol. 101 (1 Suppl.), 106S-113S (1993), S G Hillier, Clin. Endocrinol. 33(4),427-28(1990); kidney function, L. L. Hamm et al., Semin. Nephrol. 13 (1): 109-15 (1993), R C Harris, Am. J. Kidney Dis. 17(6): 627-30 (1991); tear fluid, G B van Setten et al., Int. Ophthalmol 15(6); 359-62 (1991); vitamin K mediated blood coagulation, J. Stenflo et al., Blood 78(7): 1637-51 (1991). EGF is also implicated various skin disease characterized by abnormal keratinocyte differentiation, e.g., psoriasis, epithelial cancers such as squamous cell carcinomas of the lung, epidermoid carcinoma of the vulva and gliomas. King, L E et al., Am. J. Med. Sci. 296: 154-158 (1988).
Of great interest is mounting evidence that genetic alterations in growth factors signaling pathways are closely linked to developmental abnormalities and to chronic diseases including cancer. Aaronson S A, Science 254: 1146-1153 (1991). For example, c-erb-2 (also known as HER-2), a proto-oncogene with close structural similarity to EGF receptor protein, is overexpressed in human breast cancer. King et al., Science 229: 974-976 (1985); Gullick, W J, Hormones and their actions, Cooke B A et al., eds, Amsterdam, Elsevier, pp 349-360 (1986).
17. PRO317
The TGF-β supergene family, or simply TGF-β superfamily, a group of secreted proteins, includes a large number of related growth and differentiation factors expressed in virtually all phyla. Superfamily members bind to specific cell surface receptors that activate signal transduction mechanisms to elicit their multifunctional cytokine effects. Kolodziejczyk and Hall, Biochem. Cell. Biol., 74: 299-314 (1996); Attisano and Wrana, Cytokine Growth Factor Rev., 7: 327-339 (1996); and Hill, Cellular Signaling, 8: 533-544 (1996).
Members of this family include five distinct forms of TGF-β (Sporn and Roberts, in Peptide Growth Factors and Their Receptors, Sporn and Roberts, eds. (Springer-Verlag: Berlin, 1990) pp. 419-472), as well as the differentiation factors vg1 (Weeks and Melton, Cell, 51: 861-867 (1987)) and DPP-C polypeptide (Padgett et al., Nature, 325: 81-84 (1987)), the hormones activin and inhibin (Mason et al., Nature, 318: 659-663 (1985); Mason et al., Growth Factors, 1: 77-88 (1987)), the Mullerian-inhibiting substance (MIS) (Cate et al., Cell, 45: 685-698 (1986)), the bone morphogenetic proteins (BMPs) (Wozney et al., Science, 242: 1528-1534 (1988); PCT WO 88/00205 published Jan. 14, 1988; U.S. Pat. No. 4,877,864 issued Oct. 31, 1989), the developmentally regulated proteins Vgr-1 (Lyons et al., Proc. Natl. Acad. Sci. USA. 86: 4554-4558 (1989)) and Vgr-2 (Jones et al., Molec. Endocrinol., 6: 1961-1968 (1992)), the mouse growth differentiation factor (GDF), such as GDF-3 and GDF-9 (Kingsley, Genes Dev., 8: 133-146 (1994); McPherron and Lee, J. Biol. Chem., 268: 3444-3449 (1993)), the mouse lefty/Stra1 (Meno et al., Nature, 381: 151-155 (1996); Bouillet et al., Dev. Biol., 170: 420-433 (1995)), glial cell line-derived neurotrophic factor (GDNF) (Lin et al., Science, 260: 1130-1132 (1993), neurturin (Kotzbauer et al., Nature, 384: 467-470 (1996)), and endometrial bleeding-associated factor (EBAF) (Kothapalli et al., J. Clin. Invest., 99: 2342-2350 (1997)). The subset BMP-2A and BMP-2B is approximately 75% homologous in sequence to DPP-C and may represent the mammalian equivalent of that protein.
The proteins of the TGF-β superfamily are disulfide-linked homo- or heterodimers encoded by larger precursor polypeptide chains containing a hydrophobic signal sequence, a long and relatively poorly conserved N-terminal pro region of several hundred amino acids, a cleavage site (usually polybasic), and a shorter and more highly conserved C-terminal region. This C-terminal region corresponds to the processed mature protein and contains approximately 100 amino acids with a characteristic cysteine motif, i.e., the conservation of seven of the nine cysteine residues of TGF-β among all known family members. Although the position of the cleavage site between the mature and pro regions varies among the family members, the C-terminus of all of the proteins is in the identical position, ending in the sequence Cys-X-Cys-X, but differing in every case from the TGF-β consensus C-terminus of Cys-Lys-Cys-Ser. Sporn and Roberts, 1990, supra.
There are at least five forms of TGF-β currently identified, TGF-β1, TGF-β2, TGF-β3, TGF-β4, and TGF-β5. The activated form of TGF-β1 is a homodimer formed by dimerization of the carboxy-terminal 112 amino acids of a 390 amino acid precursor. Recombinant TGF-β1 has been cloned (Derynck et al., Nature, 316:701-705 (1985)) and expressed in Chinese hamster ovary cells (Gentry et al., Mol. Cell. Biol., 7: 3418-3427 (1987)). Additionally, recombinant human TGF-β2 (deMartin et al., EMBO J., 6: 3673 (1987)), as well as human and porcine TGF-β3 (Derynck et al., EMBO J., 7: 3737-3743 (1988); ten Dijke et al., Proc. Natl. Acad. Sci. USA, 85: 4715 (1988)) have been cloned. TGF-β2 has a precursor form of 414 amino acids and is also processed to a homodimer from the carboxy-terminal 112 amino acids that shares approximately 70% homology with the active form of TGF-β1 (Marquardt et al., J. Biol. Chem., 262: 12127 (1987)). See also EP 200,341; 169,016; 268,561; and 267,463; U.S. Pat. No. 4,774,322; Cheifetz et al., Cell, 48: 409-415 (1987); Jakowlew et al., Molecular Endocrin., 2: 747-755 (1988); Derynck et al., J. Biol. Chem., 261: 4377-4379 (1986); Sharples et al., DNA, 6: 239-244 (1987); Derynck et al., Nucl. Acids. Res., 15: 3188-3189 (1987); Derynck et al., Nucl. Acids. Res., 15: 3187 (1987); Seyedin et al., J. Biol. Chem., 261: 5693-5695 (1986); Madisen et al., DNA, 7: 1-8 (1988); and Hanks et al., Proc. Natl. Acad. Sci. (U.S.A.), 85: 79-82 (1988).
TGF-β4 and TGF-β5 were cloned from a chicken chondrocyte cDNA library (Jakowlew et al., Molec. Endocrinol., 2: 1186-1195 (1988)) and from a frog oocyte cDNA library, respectively.
The pro region of TGF-β associates non-covalently with the mature TGF-β dimer (Wakefield et al., J. Biol. Chem., 263: 7646-7654 (1988); Wakefield et al., Growth Factors, 1: 203-218 (1989)), and the pro regions are found to be necessary for proper folding and secretion of the active mature dimers of both TGF-β and activin (Gray and Mason, Science, 247: 1328-1330 (1990)). The association between the mature and pro regions of TGF-β masks the biological activity of the mature dimer, resulting in formation of an inactive latent form. Latency is not a constant of the TGF-β superfamily, since the presence of the pro region has no effect on activin or inhibin biological activity.
A unifying feature of the biology of the proteins from the TGF-β superfamily is their ability to regulate developmental processes. TGF-β has been shown to have numerous regulatory actions on a wide variety of both normal and neoplastic cells. TGF-β is multifunctional, as it can either stimulate or inhibit cell proliferation, differentiation, and other critical processes in cell function (Sporn and Roberts, supra).
One member of the TGF-β superfamily, EBAF, is expressed in endometrium only in the late secretory phase and during abnormal endometrial bleeding. Kothapalli et al., J. Clin. Invest., 99: 2342-2350 (1997). Human endometrium is unique in that it is the only tissue in the body that bleeds at regular intervals. In addition, abnormal endometrial bleeding is one of the most common manifestations of gynecological diseases, and is a prime indication for hysterectomy. In situ hybridization showed that the mRNA of EBAF was expressed in the stroma without any significant mRNA expression in the endometrial glands or endothelial cells.
The predicted protein sequence of EBAF showed a strong homology to the protein encoded by mouse lefty/stra3 of the TGF-β superfamily. A motif search revealed that the predicted EBAF protein contains most of the cysteine residues which are conserved among the TGF-β-related proteins and which are necessary for the formation of the cysteine knot structure. The EBAF sequence contains an additional cysteine residue, 12 amino acids upstream from the first conserved cysteine residue. The only other family members known to contain an additional cysteine residue are TGF-βs, inhibins, and GDF-3. EBAF, similar to LEFTY, GDF-3/Vgr2, and GDF-9, lacks the cysteine residue that is known to form the intermolecular disulfide bond. Therefore, EBAF appears to be an additional member of the TGF-β superfamily with an unpaired cysteine residue that may not exist as a dimer. However, hydrophobic contacts between the two monomer subunits may promote dimer formation. Fluorescence in situ hybridization showed that the ebaf gene is located on human chromosome 1 at band q42.1.
Additional members of the TGF-β superfamily, such as those related to EBAF, are being searched for by industry and academics. We herein describe the identification and characterization of novel polypeptides having homology to EBAF, designated herein as PRO317 polypeptides.
18. PRO301
The widespread occurrence of cancer has prompted the devotion of considerable resources and discovering new treatments of treatment. One particular method involves the creation of tumor or cancer specific monoclonal antibodies (mAbs) which are specific to tumor antigens. Such mAbs, which can distinguish between normal and cancerous cells are useful in the diagnosis, prognosis and treatment of the disease. Particular antigens are known to be associated with neoplastic diseases, such as colorectal cancer.
One particular antigen, the A33 antigen is expressed in more than 90% of primary or metastatic colon cancers as well as normal colon epithelium. Since colon cancer is a widespread disease, early diagnosis and treatment is an important medical goal. Diagnosis and treatment of colon cancer can be implemented using monoclonal antibodies (mAbs) specific therefore having fluorescent, nuclear magnetic or radioactive tags. Radioactive gene, toxins and/or drug tagged mAbs can be used for treatment in situ with minimal patient description. mAbs can also be used to diagnose during the diagnosis and treatment of colon cancers. For example, when the serum levels of the A33 antigen are elevated in a patient, a drop of the levels after surgery would indicate the tumor resection was successful. On the other hand, a subsequent rise in serum A33 antigen levels after surgery would indicate that metastases of the original tumor may have formed or that new primary tumors may have appeared. Such monoclonal antibodies can be used in lieu of, or in conjunction with surgery and/or other chemotherapies. For example, U.S. Pat. No. 4,579,827 and U.S. Ser. No. 424,991 (E.P. 199,141) are directed to therapeutic administration of monoclonal antibodies, the latter of which relates to the application of anti-A33 mAb.
Many cancers of epithelial origin have adenovirus receptors. In fact, adenovirus-derived vectors have been proposed as a means of inserting antisense nucleic acids into tumors (U.S. Pat. No. 5,518,885). Thus, the association of viral receptors with neoplastic tumors is not unexpected.
We herein describe the identification and characterization of novel polypeptides having homology to certain cancer-associated antigens, designated herein as PRO301 polypeptides.
19. PRO224
Cholesterol uptake can have serious implications on one's health. Cholesterol uptake provides cells with most of the cholesterol they require for membrane synthesis. If this uptake is blocked, cholesterol accumulates in the blood and can contribute to the formation of atherosclerotic plaques in blood vessel walls. Most cholesterol is transported in the blood bound to protein in the form of complexes known as low-density lipoproteins (LDLs). LDLs are endocytosed into cells via LDL receptor proteins. Therefore, LDL receptor proteins, and proteins having homology thereto, are of interest to the scientific and medical communities.
Membrane-bound proteins and receptors can play an important role in the formation, differentiation and maintenance of multicellular organisms. The LDL receptors are an example of membrane-bound proteins which are involved in the synthesis and formation of cell membranes, wherein the health of an individual is affected directly and indirectly by its function. Many membrane-bound proteins act as receptors such as the LDL receptor. These receptors can function to endocytose substrates or they can function as a receptor for a channel. Other membrane-bound proteins function as signals or antigens.
Membrane-bound proteins and receptor molecules have various industrial applications, including as pharmaceutical and diagnostic agents. The membrane-bound proteins can also be employed for screening of potential peptide or small molecule regulators of the relevant receptor/ligand interaction. In the case of the LDL receptor, it is desirable to find molecules which enhance endocytosis so as to lower blood cholesterol levels and plaque formation. It is also desirable to identify molecules which inhibit endocytosis so that these molecules can be avoided or regulated by individuals having high blood cholesterol. Polypeptides which are homologous to lipoprotein receptors but which do not function as lipoprotein receptors are also of interest in the determination of the function of the fragments which show homology.
The following studies report on previously known low density lipoprotein receptors and related proteins including apolipoproteins: Sawamura, et al., Nippon Chemiphar Co, Japan patent application J09098787; Novak, S., et al., J. Biol. Chem., 271: (20)11732-6 (1996); Blaas, D., J. Virol., 69(11)7244-7 (November 1995); Scott, J., J. Inherit. Metab. Dis. (UK), 9/Supp. 1 (3-16) (1986); Yamamoto, et al., Cell, 39:27-38 (1984); Rebece, et al., Neurobiol. Aging, 15:5117(1994); Novak, S., et al., J. Biol. Chemistry, 271:11732-11736(1996); and Sestavel and Fruchart, Cell Mol. Biol., 40(4):461-81 (June 1994). These publications and others published prior to the filing of this application provide further background to peptides already known in the art.
Efforts are being undertaken by both industry and academia to identify new, native membrane-bound receptor proteins, particularly those having homology to lipoprotein receptors. We herein describe the identification and characterization of novel polypeptides having homology to lipoprotein receptors, designated herein as PRO224 polypeptides.
20. PRO222
Complement is a group of proteins found in the blood that are important in humoral immunity and inflammation. Complement proteins are sequentially activated by antigen-antibody complexes or by proteolytic enzymes. When activated, complement proteins kill bacteria and other microorganisms, affect vascular permeability, release histamine and attract white blood cells. Complement also enhances phagocytosis when bound to target cells. In order to prevent harm to autologous cells, the complement activation pathway is tightly regulated.
Deficiencies in the regulation of complement activation or in the complement proteins themselves may lead to immune-complex diseases, such as systemic lupus erythematosus, and may result in increased susceptibility to bacterial infection. In all cases, early detection of complement deficiency is desirable so that the patient can begin treatment. Thus, research efforts are currently directed toward identification of soluble and membrane proteins that regulate complement activation.
Proteins known to be important in regulating complement activation in humans include Factor H and Complement receptor type 1 (CR1). Factor H is a 150 kD soluble serum protein that interacts with complement protein C3b to accelerate the decay of C3 convertase and acts as a cofactor for Factor I-mediated cleavage of complement protein C4b. Complement receptor type 1 is a 190-280 kD membrane bound protein found in mast cells and most blood cells. CR1 interacts with complement proteins C3b, C4b, and C3b to accelerate dissociation of C3 convertases, acts as a cofactor for Factor I-mediated cleavage of C3b and C4b, and binds immune complexes and promotes their dissolution and phagocytosis.
Proteins which have homology to complement proteins are of particular interest to the medical and industrial communities. Often, proteins having homology to each other have similar function. It is also of interest when proteins having homology do not have similar functions, indicating that certain structural motifs identify information other than function, such as locality of function.
Efforts are being undertaken by both industry and academia to identify new, native secreted and membrane-bound proteins, particularly those having homology to known proteins involved in the complement pathway. Proteins involved in the complement pathway were reviewed in Birmingham D J (1995), Critical Reviews in Immunology, 15(2):133-154 and in Abbas A K, et al. (1994) Cellular and Molecular Immunology, 2nd Ed. W. B. Saunders Company, Philadelphia, pp 295-315.
We herein describe the identification and characterization of novel polypeptides having homology to complement receptors, designated herein as PRO222 polypeptides.
21. PRO234
The successful function of many systems within multicellular organisms is dependent on cell-cell interactions. Such interactions are affected by the alignment of particular ligands with particular receptors in a manner which allows for ligand-receptor binding and thus a cell-cell adhesion. While protein-protein interactions in cell recognition have been recognized for some time, only recently has the role of carbohydrates in physiologically relevant recognition been widely considered (see B. K. Brandley et al., J. Leuk. Biol. 40: 97 (1986) and N. Sharon et al., Science 246: 227 (1989). Oligosaccharides are well positioned to act as recognition novel lectins due to their cell surface location and structural diversity. Many oligosaccharide structures can be created through the differential activities of a smaller number of glycosyltransferases. The diverse structures of oligosaccharides can be generated by transcription of relatively few gene products, which suggests that the oligosaccharides are a plausible mechanism by which is directed a wide range of cell-cell interactions. Examples of differential expression of cell surface carbohydrates and putative carbohydrate binding proteins (lectins) on interacting cells have been described (J. Dodd & T. M. Jessel, J. Neurosci. 5: 3278 (1985); L. J. Regan et al., Proc. Natl. Acad. Sci. USA 83: 2248 (1986); M. Constantine-Paton et al., Nature 324: 459 (1986); and M. Tiemeyer et al., J. Biol. Chem. 263: 1671 (1989). One interesting member of the lectin family are selectins.
The migration of leukocytes to sites of acute or chronic inflammation involves adhesive interactions between these cells and the endothelium. This specific adhesion is the initial event in the cascade that is initiated by inflammatory insults, and it is, therefore, of paramount importance to the regulated defense of the organism.
The types of cell adhesion molecules that are involved in the interaction between leukocytes and the endothelium during an inflammatory response currently stands at four: (1) selectins; (2) (carbohydrate and glycoprotein) ligands for selecting; (3) integrins; and (4) integrin ligands, which are members of the immunoglobulin gene superfamily.
The selectins are cell adhesion molecules that are unified both structurally and functionally. Structurally, selectins are characterized by the inclusion of a domain with homology to a calcium-dependent lectin (C-lectins), an epidermal growth factor (egf)-like domain and several complement binding-like domains, Bevilacqua, M. P. et al., Science 243: 1160-1165 (1989); Johnston et al., Cell 56: 1033-1044 (1989); Lasky et al, Cell 56: 1045-1055 (1989); Siegalman, M. et al., Science 243: 1165-1172 (1989); Stoolman, L. M., Cell 56: 907-910 (1989). Functionally, selectins share the common property of their ability to mediate cell binding through interactions between their lectin domains and cell surface carbohydrate ligands (Brandley, B, et al., Cell 63, 861-863 (1990); Springer, T. and Lasky, L. A., Nature 349, 19-197 (1991); Bevilacqua, M. P. and Nelson, R. M., J. Clin. Invest. 91 379-387 (1993) and Tedder et al., J. Exp. Med. 170: 123-133 (1989).
There are three members identified so far in the selectin family of cell adhesion molecules: L-selectin (also called peripheral lymph node homing receptor (pnHR), LEC-CAM-1, LAM-1, gp90MEL, gp100MEL, gp110MEL, MEL-14 antigen, Leu-8 antigen, TQ-1 antigen, DREG antigen), E-selectin (LEC-CAM-2, LECAM-2, ELAM-1) and P-selectin (LEC-CAM-3, LECAM-3, GMP-140, PADGEM).
The identification of the C-lectin domain has led to an intense effort to define carbohydrate binding ligands for proteins containing such domains. E-selectin is believed to recognize the carbohydrate sequence NeuNAcα2-3Galβ1-4(Fucα1-3) GlcNAc (sialyl-Lewis x, or sLex) and related oligosaccharides, Berg et al., J. Biol. Chem. 265: 14869-14872 (1991); Lowe et al., Cell 63: 475-484 (1990); Phillips et al., Science 250: 1130-1132(1990); Tiemeyer et al., Proc. Natl. Acad. Sci. USA 88: 1138-1142(1991).
L-selectin, which comprises a lectin domain, performs its adhesive function by recognizing carbohydrate-containing ligands on endothelial cells. L-selectin is expressed on the surface of leukocytes, such as lymphocytes, neutrophils, monocytes and eosinophils, and is involved with the trafficking of lymphocytes to peripheral lymphoid tissues (Gallatin et al., Nature 303: 30-34 (1983)) and with acute neutrophil-medicated inflammatory responses (Watson, S. R., Nature 349: 164-167 (1991)). The amino acid sequence of L-selectin and the encoding nucleic acid sequence are, for example, disclosed in U.S. Pat. No. 5,098,833 issued Mar. 24, 1992.
L-selectin (LECAM-1) is particularly interesting because of its ability to block neutrophil influx (Watson et al., Nature 349: 164-167 (1991). It is expressed in chronic lymphocytic leukemia cells which bind to HEV (Spertini et al., Nature 349: 691-694 (1991). It is also believed that HEV structures at sites of chronic inflammation are associated with the symptoms of diseases such as rheumatoid arthritis, psoriasis and multiple sclerosis.
E-selectin (ELAM-1), is particularly interesting because of its transient expression on endothelial cells in response to IL-1 or TNF. Bevilacqua et al., Science 243: 1160 (1989). The time course of this induced expression (2-8 h) suggests a role for this receptor in initial neutrophil induced extravasation in response to infection and injury. It has further been reported that anti-ELAM-1 antibody blocks the influx of neutrophils in a primate asthma model and thus is beneficial for preventing airway obstruction resulting from the inflammatory response. Gundel et al., J. Clin. Invest. 88: 1407 (1991).
The adhesion of circulating neutrophils to stimulated vascular endothelium is a primary event of the inflammatory response. P-selectin has been reported to recognize the Lewis x structure (Galβ1-4(Fucα1-3) GlcNAc), Larsen et al., Cell 63: 467-474(1990). Others report that an additional terminal linked sialic acid is required for high affinity binding, Moore et al., J. Cell. Biol. 112: 491-499 (1991). P-selectin has been shown to be significant in acute lung injury. Anti-P-selectin antibody has been shown to have strong protective effects in a rodent lung injury model. M. S. Mulligan et al., J. Clin. Invest. 90: 1600 (1991).
We herein describe the identification and characterization of novel polypeptides having homology to lectin proteins, herein designated as PRO234 polypeptides.
22. PRO231
Some of the most important proteins involved in the above described regulation and modulation of cellular processes are the enzymes which regulate levels of protein phosphorylation in the cell. For example, it is known that the transduction of signals that regulate cell growth and differentiation is regulated at least in part by phosphorylation and dephosphorylation of various cellular proteins. The enzymes that catalyze these processes include the protein kinases, which function to phosphorylate various cellular proteins, and the protein phosphatases, which function to remove phosphate residues from various cellular proteins. The balance of the level of protein phosphorylation in the cell is thus mediated by the relative activities of these two types of enzymes.
Protein phosphatases represent a growing family of enzymes that are found in many diverse forms, including both membrane-bound and soluble forms. While many protein phosphatases have been described, the functions of only a very few are beginning to be understood (Tonks, Semin. Cell Biol. 4:373-453 (1993) and Dixon, Recent Prog. Horm. Res. 51:405-414 (1996)). However, in general, it appears that many of the protein phosphatases function to modulate the positive or negative signals induced by various protein kinases. Therefore, it is likely that protein phosphatases play critical roles in numerous and diverse cellular processes.
Given the physiological importance of the protein phosphatases, efforts are being undertaken by both industry and academia to identify new, native phosphatase proteins. Many of these efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel phosphatase proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We herein describe the identification and characterization of novel polypeptides having homology to acid phosphatases, designated herein as PRO231 polypeptides.
23. PRO229
Scavenger receptors are known to protect IgG molecules from catabolic degradation. Riechmann and Hollinger, Nature Biotechnology, 15:617 (1997). In particular, studies of the CH2 and CH3 domains have shown that specific sequences of these domains are important in determining the half-lives of antibodies. Ellerson, et al., J. Immunol., 116: 510 (1976); Yasmeen, et al., J. Immunol. 116: 518 (1976; Pollock, et al., Eur. J. Immunol., 20: 2021 (1990). Scavenger receptor proteins and antibodies thereto are further reported in U.S. Pat. No. 5,510,466 to Krieger, et al. Due to the ability of scavenger receptors to increase the half-life of polypeptides and their involvement in immune function, molecules having homology to scavenger receptors are of importance to the scientific and medical community.
Efforts are being undertaken by both industry and academia to identify new, native secreted and membrane-bound receptor proteins, particularly those having homology to scavenger receptors. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound receptor proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We herein describe the identification and characterization of novel polypeptides having homology to scavenger receptors, designated herein as PRO229 polypeptides.
24. PRO238
Oxygen free radicals and antioxidants appear to play an important role in the central nervous system after cerebral ischemia and reperfusion. Moreover, cardiac injury, related to ischaemia and reperfusion has been reported to be caused by the action of free radicals. Additionally, studies have reported that the redox state of the cell is a pivotal determinant of the fate of the cells. Furthermore, reactive oxygen species have been reported to be cytotoxic, causing inflammatory disease, including tissue necrosis, organ failure, atherosclerosis, infertility, birth defects, premature aging, mutations and malignancy. Thus, the control of oxidation and reduction is important for a number of reasons including for control and prevention of strokes, heart attacks, oxidative stress and hypertension. In this regard, reductases, and particularly, oxidoreductases, are of interest. Publications further describing this subject matter include Kelsey, et al., Br. J. Cancer, 76(7):8524 (1997); Friedrich and Weiss, J. Theor. Biol., 187(4):52940 (1997) and Pieulle, et al., J. Bacteriol., 179(18):5684-92 (1997).
Efforts are being undertaken by both industry and academia to identify new, native secreted and membrane-bound receptor proteins, particularly secreted proteins which have homology to reductase. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound receptor proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We herein describe the identification and characterization of novel polypeptides having homology to reductase, designated herein as PRO238 polypeptides.
25. PRO233
Studies have reported that the redox state of the cell is an important determinant of the fate of the cell. Furthermore, reactive oxygen species have been reported to be cytotoxic, causing inflammatory disease, including tissue necrosis, organ failure, atherosclerosis, infertility, birth defects, premature aging, mutations and malignancy. Thus, the control of oxidation and reduction is important for a number of reasons, including the control and prevention of strokes, heart attacks, oxidative stress and hypertension. Oxygen free radicals and antioxidants appear to play an important role in the central nervous system after cerebral ischemia and reperfusion. Moreover, cardiac injury, related to ischaemia and reperfusion has been reported to be caused by the action of free radicals. In this regard, reductases, and particularly, oxidoreductases, are of interest. In addition, the transcription factors, NF-kappa B and AP-1, are known to be regulated by redox state and to affect the expression of a large variety of genes thought to be involved in the pathogenesis of AIDS, cancer, atherosclerosis and diabetic complications. Publications further describing this subject matter include Kelsey, et al., Br. J. Cancer, 76(7):8524 (1997); Friedrich and Weiss, J. Theor. Biol., 187(4):529-40 (1997) and Pieulle, et al., J. Bacteriol., 179(18):5684-92 (1997). Given the physiological importance of redox reactions in vivo, efforts are currently being under taken to identify new, native proteins which are involved in redox reactions. We describe herein the identification of novel polypeptides which have homology to reductase, designated herein as PRO233 polypeptides.
26. PRO223
The carboxypeptidase family of exopeptidases constitutes a diverse group of enzymes that hydrolyze carboxyl-terminal amide bonds in polypeptides, wherein a large number of mammalian tissues produce these enzymes. Many of the carboxypeptidase enzymes that have been identified to date exhibit rather strong cleavage specificities for certain amino acids in polypeptides. For example, carboxypeptidase enzymes have been identified which prefer lysine, arginine, serine or amino acids with either aromatic or branched aliphatic side chains as substrates at the carboxyl terminus of the polypeptide.
With regard to the serine carboxypeptidases, such amino acid specific enzymes have been identified from a variety of different mammalian and non-mammalian organisms. The mammalian serine carboxypeptidase enzymes play important roles in many different biological processes including, for example, protein digestion, activation, inactivation, or modulation of peptide hormone activity, and alteration of the physical properties of proteins and enzymes.
In light of the physiological importance of the serine carboxypeptidases, efforts are being undertaken by both industry and academia to identify new, native secreted and membrane-bound receptor proteins and specifically novel carboxypeptidases. Many of these efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound receptor proteins. We describe herein novel polypeptides having homology to one or more serine carboxypeptidase polypeptides, designated herein as PRO223 polypeptides.
27. PRO235
Plexin was first identified in Xenopus tadpole nervous system as a membrane glycoprotein which was shown to mediate cell adhesion via a homophilic binding mechanism in the presence of calcium ions. Strong evolutionary conservation between Xenopus, mouse and human homologs of plexin has been observed. [Kaneyama et al., Biochem. And Biophys. Res. Comm. 226: 52 4529 (1996)]. Given the physiological importance of cell adhesion mechanisms in vivo, efforts are currently being under taken to identify new, native proteins which are involved in cell adhesion. We describe herein the identification of a novel polypeptide which has homology to plexin, designated herein as PRO235.
28. PRO236 and PRO262
β-galactosidase is a well known enzymatic protein which functions to hydrolyze β-galactoside molecules. β-galactosidase has been employed for a variety of different applications, both in vitro and in vivo and has proven to be an extremely useful research tool. As such, there is an interest in obtaining novel polypeptides which exhibit homology to the β-galactosidase polypeptide.
Given the strong interest in obtaining novel polypeptides having homology to β-galactosidase, efforts are currently being undertaken by both industry and academia to identify new, native β-galactosidase homolog proteins. Many of these efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel β-galactosidase-like proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)]. We herein describe novel poylpeptides having siginificant homology to the β-galactosidase enzyme, designated herein as PRO236 and PRO262 polypeptides.
29. PRO239
Densin is a glycoprotein which has been isolated from the brain which has all the hallmarks of an adhesion molecule. It is highly concentrated at synaptic sites in the brain and is expressed prominently in dendritic processes in developing neurons. Densin has been characterized as a member of the O-linked sialoglycoproteins. Densin has relevance to medically important processes such as regeneration. Given the physiological importance of synaptic processes and cell adhesion mechanisms in vivo, efforts are currently being under taken to identify new, native proteins which are involved in synaptic machinery and cell adhesion. We describe herein the identification of novel polypeptides which have homology to densin, designated herein as PRO239 polypeptides.
30. PRO257
Ebnerin is a cell surface protein associated with von Ebner glands in mammals. Efforts are being undertaken by both industry and academia to identify new, native cell surface receptor proteins and specifically those which possess sequence homology to cell surface proteins such as ebnerin. Many of these efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel receptor proteins. We herein describe the identification of novel polypeptides having significant homology to the von Ebner's gland-associated protein ebnerin, designated herein as PRO257 polypeptides.
31. PRO260
Fucosidases are enzymes that remove fucose residues from fucose containing proteoglycans. In some pathological conditions, such as cancer, rheumatoid arthritis, and diabetes, there is an abnormal fucosylation of serum proteins. Therefore, fucosidases, and proteins having homology to fucosidase, are of importance to the study and abrogation of these conditions. In particular, proteins having homology to the alpha-1-fucosidase precursor are of interest. Fucosidases and fucosidase inhibitors are further described in U.S. Pat. Nos. 5,637,490, 5,382,709, 5,240,707, 5,153,325, 5,100,797, 5,096,909 and 5,017,704. Studies are also reported in Valk, et al., J. Virol., 71(9):6796 (1997), Aktogu, et al., Monaldi. Arch. Chest Dis. (Italy), 52(2):118 (1997) and Focarelli, et al., Biochem. Biophys. Res. Commun. (U.S.), 234(1):54 (1997).
Efforts are being undertaken by both industry and academia to identify new, native secreted and membrane-bound receptor proteins. Of particular interest are proteins having homology to the alpha-1-fucosidase precursor. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound receptor proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We herein describe the identification and characterization of novel polypeptides having homology to fucosidases, designated herein as PRO260 polypeptides.
32. PRO263
CD44 is a cell surface adhesion molecule involved in cell-cell and cell-matrix interactions. Hyaluronic acid, a component of the extracellular matrix is a major ligand. Other ligands include collagen, fibronectin, laminin, chrondroitin sulfate, mucosal addressin, serglycin and osteoponin. CD44 is also important in regulating cell traffic, lymph node homing, transmission of growth signals, and presentation of chemokines and growth factors to traveling cells. CD44 surface proteins are associated with metastatic tumors and CD44 has been used as a marker for HIV infection. Certain splice variants are associated with metastasis and poor prognosis of cancer patients. Therefore, molecules having homology with CD44 are of particular interest, as their homology indicates that they may have functions related to those functions of CD44. CD44 is further described in U.S. Pat. Nos. 5,506,119, 5,504,194 and 5,108,904; Gerberick, et al., Toxicol. Appl. Pharmacol., 146(1):1 (1997); Wittig, et al., Immunol. Letters (Netherlands), 57(1-3):217 (1997); and Oliveira and Odell, Oral Oncol. (England), 33(4):260 (1997).
Efforts are being undertaken by both industry and academia to identify new, native secreted and membrane-bound receptor proteins, particularly transmembrane proteins with homology to CD44 antigen. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound receptor proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We herein describe the identification and characterization of novel polypeptides having homology to CD44 antigen, designated herein as PRO263 polypeptides.
33. PRO270
Thioredoxins effect reduction-oxidation (redox) state. Many diseases are potentially related to redox state and reactive oxygen species may play a role in many important biological processes. The transcription factors, NF-kappa B and AP-1, are regulated by redox state and are known to affect the expression of a large variety of genes thought to be involved in the pathogenesis of AIDS, cancer, atherosclerosis and diabetic complications. Such proteins may also play a role in cellular antioxidant defense, and in pathological conditions involving oxidative stress such as stroke and inflammation in addition to having a role in apoptosis. Therefore, thioredoxins, and proteins having homology thereto, are of interest to the scientific and medical communities.
We herein describe the identification and characterization of novel polypeptides having homology to thioredoxin, designated herein as PRO270 polypeptides.
34. PRO271
The proteoglycan link protein is a protein which is intimately associated with various extracellular matrix proteins and more specifically with proteins such as collagen. For example, one primary component of collagen is a large proteoglycan called aggrecan. This molecule is retained by binding to the glycosaminoglycan hyaluronan through the amino terminal G1 globular domain of the core protein. This binding is stabilized by the proteoglycan link protein which is a protein that is also associated with other tissues containing hyaluronan binding proteoglycans such as versican.
Link protein has been identified as a potential target for autoimmune antibodies in individuals who suffer from juvenile rheumatoid arthritis (see Guerassimov et al., J. Rheumatology 24(5):959-964 (1997)). As such, there is strong interest in identifying novel proteins having homology to link protein. We herein describe the identification and characterization of novel polypeptides having such homology, designated herein as PRO271 polypeptides.
35. PRO272
Reticulocalbin is an endoplasmic reticular protein which may be involved in protein transport and luminal protein processing. Reticulocalbin resides in the lumen of the endoplasmic rerticulum, is known to bind calcium, and may be involved in a luminal retention mechanism of the endoplasmic reticulum. It contains six domains of the EF-hand motif associated with high affinity calcium binding. We describe herein the identification and characterization of a novel polypeptide which has homology to the reticulocalbin protein, designated herein as PRO272.
36. PRO294
Collagen, a naturally occurring protein, finds wide application in industry. Chemically hydrolyzed natural collagen can be denatured and renatured by heating and cooling to produce gelatin, which is used in photographic and medical, among other applications. Collagen has important properties such as the ability to form interchain aggregates having a conformation designated as a triple helix. We herein describe the identification and characterization of a novel polypeptide which has homology to portions of the collagen molecule, designated herein as PRO294.
37. PRO295
The integrins comprise a supergene family of cell-surface glycoprotein receptors that promote cellular adhesion. Each cell has numerous receptors that define its cell adhesive capabilities. Integrins are involved in a wide variety of interaction between cells and other cells or matrix components. The integrins are of particular importance in regulating movement and function of immune system cells The platelet IIb/IIIA integrin complex is of particular importance in regulating platelet aggregation. A member of the integrin family, integrin β-6, is expressed on epithelial cells and modulates epithelial inflammation. Another integrin, leucocyte-associated antigen-1 (LFA-1) is important in the adhesion of lymphocytes during an immune response. The integrins are expressed as heterodimers of non-covalently associated alpha and beta subunits. Given the physiological importance of cell adhesion mechanisms in vivo, efforts are currently being under taken to identify new, native proteins which are involved in cell adhesion. We describe herein the identification and characterization of a novel polypeptide which has homology to integrin, designated herein as PRO295.
38. PRO293
Protein-protein interactions include receptor and antigen complexes and signaling mechanisms. As more is known about the structural and functional mechanisms underlying protein-protein interactions, protein-protein interactions can be more easily manipulated to regulate the particular result of the protein-protein interaction. Thus, the underlying mechanisms of protein-protein interactions are of interest to the scientific and medical community.
All proteins containing leucine-rich repeats are thought to be involved in protein-protein interactions. Leucine-rich repeats are short sequence motifs present in a number of proteins with diverse functions and cellular locations. The crystal structure of ribonuclease inhibitor protein has revealed that leucine-rich repeats correspond to beta-alpha structural units. These units are arranged so that they form a parallel beta-sheet with one surface exposed to solvent, so that the protein acquires an unusual, nonglubular shape. These two features have been indicated as responsible for the protein-binding functions of proteins containing leucine-rich repeats. See, Kobe and Deisenhofer, Trends Biochem. Sci., 19(10):415-421 (October 1994).
A study has been reported on leucine-rich proteoglycans which serve as tissue organizers, orienting and ordering collagen fibrils during ontogeny and are involved in pathological processes such as wound healing, tissue repair, and tumor stroma formation. Iozzo, R. V., Crit. Rev. Biochem. Mol. Biol., 32(2):141-174 (1997). Others studies implicating leucine rich proteins in wound healing and tissue repair are De La Salle, C., et al., Vouv. Rev. Fr. Hematol. (Germany), 37(4):215-222 (1995), reporting mutations in the leucine rich motif in a complex associated with the bleeding disorder Bernard-Soulier syndrome and Chlemetson, K. J., Thromb. Haemost. (Germany), 74(1): 111-116 (July 1995), reporting that platelets have leucine rich repeats. Another protein of particular interest which has been reported to have leucine-rich repeats is the SLIT protein which has been reported to be useful in treating neuro-degenerative diseases such as Alzheimer's disease, nerve damage such as in Parkinson's disease, and for diagnosis of cancer, see, Artavanistsakonas, S. and Rothberg, J. M., WO9210518-A1 by Yale University. Other studies reporting on the biological functions of proteins having leucine-rich repeats include: Tayar, N., et al., Mol. Cell Endocrinol., (Ireland), 125(1-2):65-70 (December 1996) (gonadotropin receptor involvement); Miura, Y., et al., Nippon Rinsho (Japan), 54(7):1784-1789 (July 1996) (apoptosis involvement); Harris, P. C., et al., J. Am. Soc. Nephrol., 6(4):1125-1133 (October 1995) (kidney disease involvement); and Ruoslahti, E. I., et al., WO9110727-A by La Jolla Cancer Research Foundation (decorin binding to transforming growth factorβ involvement for treatment for cancer, wound healing and scarring).
Efforts are therefore being undertaken by both industry and academia to identify new proteins having leucine rich repeats to better understand protein-protein interactions. Of particular interest are those proteins having leucine rich repeats and homology to known neuronal leucine rich repeat proteins. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound proteins having leucine rich repeats. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We describe herein the identification and characterization of a novel polypeptide which has homology to leucine rich repeat proteins, designated herein as PRO293.
39. PRO247
Protein-protein interactions include receptor and antigen complexes and signaling mechanisms. As more is known about the structural and functional mechanisms underlying protein-protein interactions, protein-protein interactions can be more easily manipulated to regulate the particular result of the protein-protein interaction. Thus, the underlying mechanisms of protein-protein interactions are of interest to the scientific and medical community.
All proteins containing leucine-rich repeats are thought to be involved in protein-protein interactions. Leucine-rich repeats are short sequence motifs present in a number of proteins with diverse functions and cellular locations. The crystal structure of ribonuclease inhibitor protein has revealed that leucine-rich repeats correspond to beta-alpha structural units. These units are arranged so that they form a parallel beta-sheet with one surface exposed to solvent, so that the protein acquires an unusual, nonglubular shape. These two features have been indicated as responsible for the protein-binding functions of proteins containing leucine-rich repeats. See, Kobe and Deisenhofer, Trends Biochem. Sci., 19(10):415-421 (October 1994).
A study has been reported on leucine-rich proteoglycans which serve as tissue organizers, orienting and ordering collagen fibrils during ontogeny and are involved in pathological processes such as wound healing, tissue repair, and tumor stroma formation. Iozzo, R. V., Crit. Rev. Biochem. Mol. Biol., 32(2):141-174 (1997). Others studies implicating leucine rich proteins in wound healing and tissue repair are De La Salle, C., et al., Vouv. Rev. Fr. Hematol. (Germany), 37(4):215-222 (1995), reporting mutations in the leucine rich motif in a complex associated with the bleeding disorder Bernard-Soulier syndrome and Chlemetson, K. J., Thromb. Haemost. (Germany), 74(1):111-116 (July 1995), reporting that platelets have leucine rich repeats. Another protein of particular interest which has been reported to have leucine-rich repeats is the SLIT protein which has been reported to be useful in treating neuro-degenerative diseases such as Alzheimer's disease, nerve damage such as in Parkinson's disease, and for diagnosis of cancer, see, Artavanistsakonas, S. and Rothberg, J. M., WO9210518-A1 by Yale University. Other studies reporting on the biological functions of proteins having leucine-rich repeats include: Tayar, N., et al., Mol. Cell Endocrinol., (Ireland), 125(1-2):65-70 (December 1996) (gonadotropin receptor involvement); Miura, Y., et al., Nippon Rinsho (Japan), 54(7): 1784-1789 (July 1996) (apoptosis involvement); Harris, P. C., et al., J. Am. Soc. Nephrol., 6(4):1125-1133 (October 1995) (kidney disease involvement); and Ruoslahti, E. I., et al., WO9110727-A by La Jolla Cancer Research Foundation (decorin binding to transforming growth factors involvement for treatment for cancer, wound healing and scarring).
Densin is a glycoprotein which has been isolated from the brain which has all the hallmarks of an adhesion molecule. It is highly concentrated at synaptic sites in the brain and is expressed prominently in dendritic processes in developing neurons. Densin has been characterized as a member of the O-linked sialoglycoproteins. Densin has relevance to medically important processes such as regeneration. Given the physiological importance of synaptic processes and cell adhesion mechanisms in vivo, efforts are currently being under taken to identify new, native proteins which are involved in synaptic machinery and cell adhesion. Densin is further described in Kennedy, M. B, Trends Neurosci. (England), 20(6):264 (1997) and Apperson, et al., J. Neurosci., 16(21):6839 (1996).
Efforts are therefore being undertaken by both industry and academia to identify new proteins having leucine rich repeats to better understand protein-protein interactions. Of particular interest are those proteins having leucine rich repeats and homology to known proteins having leucine rich repeats such as KIAA0231 and densin. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound proteins having leucine rich repeats. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We describe herein the identification and characterization of a novel polypeptide which has homology to leucine rich repeat proteins, designated herein as PRO247.
40. PRO302, PRO303, PRO304, PRO307 and PRO343
Proteases are enzymatic proteins which are involved in a large number of very important biological processes in mammalian and non-mammalian organisms. Numerous different protease enzymes from a variety of different mammalian and non-mammalian organisms have been both identified and characterized. The mammalian protease enzymes play important roles in many different biological processes including, for example, protein digestion, activation, inactivation, or modulation of peptide hormone activity, and alteration of the physical properties of proteins and enzymes.
In light of the important physiological roles played by protease enzymes, efforts are currently being undertaken by both industry and academia to identify new, native protease homologs. Many of these efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound receptor proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)]. We herein describe the identification of novel polypeptides having homology to various protease enzymes, designated herein as PRO302, PRO303, PRO304, PRO307 and PRO343 polypeptides.
41. PRO328
The GLIP protein family has been characterized as comprising zinc-finger proteins which play important roles in embryogenesis. These proteins may function as transcriptional regulatory proteins and are known to be amplified in a subset of human tumors. Glioma pathogenesis protein is structurally related to a group of plant pathogenesis-related proteins. It is highly expressed in glioblastoma. See U.S. Pat. No. 5,582,981 (issued Dec. 10, 1996) and U.S. Pat. No. 5,322,801 (issued Jun. 21, 1996), Ellington, A. D. et al., Nature, 346:818 (1990), Grindley, J. C. et al., Dev. Biol., 188(2):337 (1997), Marine, J. C. et al., Mech. Dev., 63(2):211 (1997), The CRISP or cysteine rich secretory protein family are a group of proteins which are also structurally related to a group of plant pathogenesis proteins. [Schwidetzky, U., Biochem. J., 321:325 (1997), Pfisterer, P., Mol. Cell Biol., 16(11):6160 (1996), Kratzschmar, J. Eur. J. Biochem., 236(3):827 (1996)]. We describe herein the identification of a novel polypeptide which has homology to GLIP and CRISP, designated herein as PRO328 polypeptides.
42. PRO335, PRO331 and PRO326
Protein-protein interactions include receptor and antigen complexes and signaling mechanisms. As more is known about the structural and functional mechanisms underlying protein-protein interactions, protein-protein interactions can be more easily manipulated to regulate the particular result of the protein-protein interaction. Thus, the underlying mechanisms of protein-protein interactions are of interest to the scientific and medical community.
All proteins containing leucine-rich repeats are thought to be involved in protein-protein interactions. Leucine-rich repeats are short sequence motifs present in a number of proteins with diverse functions and cellular locations. The crystal structure of ribonuclease inhibitor protein has revealed that leucine-rich repeats correspond to beta-alpha structural units. These units are arranged so that they form a parallel beta-sheet with one surface exposed to solvent, so that the protein acquires an unusual, nonglubular shape. These two features have been indicated as responsible for the protein-binding functions of proteins containing leucine-rich repeats. See, Kobe and Deisenhofer, Trends Biochem. Sci., 19(10):415421 (October 1994).
A study has been reported on leucine-rich proteoglycans which serve as tissue organizers, orienting and ordering collagen fibrils during ontogeny and are involved in pathological processes such as wound healing, tissue repair, and tumor stroma formation. Iozzo, R. V., Crit. Rev. Biochem. Mol. Biol., 32(2):141-174 (1997). Others studies implicating leucine rich proteins in wound healing and tissue repair are De La Salle, C., et al., Vouv. Rev. Fr. Hematol. (Germany), 37(4):215-222 (1995), reporting mutations in the leucine rich motif in a complex associated with the bleeding disorder Bernard-Soulier syndrome, Chlemetson, K. J., Thromb. Haemost. (Germany), 74(1): 111-116 (July 1995), reporting that platelets have leucine rich repeats and Ruoslahti, E. I., et al., WO9110727-A by La Jolla Cancer Research Foundation reporting that decorin binding to transforming growth factorβ has involvement in a treatment for cancer, wound healing and scarring. Related by function to this group of proteins is the insulin like growth factor (IGF), in that it is useful in wound-healing and associated therapies concerned with re-growth of tissue, such as connective tissue, skin and bone; in promoting body growth in humans and animals; and in stimulating other growth-related processes. The acid labile subunit of IGF (ALS) is also of interest in that it increases the half-life of IGF and is part of the IGF complex in vivo.
Another protein which has been reported to have leucine-rich repeats is the SLIT protein which has been reported to be useful in treating neuro-degenerative diseases such as Alzheimer's disease, nerve damage such as in Parkinson's disease, and for diagnosis of cancer, see, Artavanistsakonas, S. and Rothberg, J. M., WO9210518-A1 by Yale University. Of particular interest is LIG-1, a membrane glycoprotein that is expressed specifically in glial cells in the mouse brain, and has leucine rich repeats and immunoglobulin-like domains. Suzuki, et al., J. Biol. Chem. (U.S.), 271(37):22522 (1996). Other studies reporting on the biological functions of proteins having leucine rich repeats include: Tayar, N., et al., Mol. Cell Endocrinol., (Ireland), 125(1-2):65-70 (December 1996) (gonadotropin receptor involvement); Miura, Y., et al., Nippon Rinsho (Japan), 54(7):1784-1789 (July 1996) (apoptosis involvement); Harris, P. C., et al., J. Am. Soc. Nephrol., 6(4):1125-1133 (October 1995) (kidney disease involvement).
Efforts are therefore being undertaken by both industry and academia to identify new proteins having leucine rich repeats to better understand protein-protein interactions. Of particular interest are those proteins having leucine rich repeats and homology to known proteins having leucine rich repeats such as LIG-1, ALS and decorin. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound proteins having leucine rich repeats. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We describe herein the identification and characterization of novel polypeptides which have homology to proteins of the leucine rich repeat superfamily, designated herein as PRO335, PRO331 and PRO326 polypeptides.
43. PRO332
Secreted proteins comprising a repeat characterized by an arrangement of conserved leucine residues (leucine-rich repeat motif) have diverse biological roles. Certain proteoglycans, such as biglycan, fibromodulin and decorin, are, for example, characterized by the presence of a leucine-rich repeat of about 24 amino acids [Ruoslahti, Ann. Rev. Cell. Biol. 4 229-255 (1988); Oldberg et al., EMBO J. 8, 2601-2604 (1989)]. In general, proteoglycans are believed to play a role in regulating extracellular matrix, cartilage or bone function. The proteoglycan decorin binds to collagen type I and II and affects the rate of fibril formation. Fibromodulin also binds collagen and delays fibril formation. Both fibromodulin and decorin inhibit the activity of transforming growth factor beta (TGF-β) (U.S. Pat. No. 5,583,103 issued Dec. 10, 1996). TGF-β is known to play a key role in the induction of extracellular matrix and has been implicated in the development of fibrotic diseases, such as cancer and glomerulonephritis. Accordingly, proteoglycans have been proposed for the treatment of fibrotic cancer, based upon their ability to inhibit TGF-β's growth stimulating activity on the cancer cell. Proteoglycans have also been described as potentially useful in the treatment of other proliferative pathologies, including rheumatoid arthritis, arteriosclerosis, adult respiratory distress syndrome, cirrhosis of the liver, fibrosis of the lungs, post-myocardial infarction, cardiac fibrosis, post-angioplasty restenosis, renal interstitial fibrosis and certain dermal fibrotic conditions, such as keloids and scarring, which might result from burn injuries, other invasive skin injuries, or cosmetic or reconstructive surgery (U.S. Pat. No. 5,654,270, issued Aug. 5, 1997).
We describe herein the identification and characterization of novel polypeptides which have homology to proteins of the leucine rich repeat superfamily, designated herein as PRO332 polypeptides.
44. PRO334
Microfibril bundles and proteins found in association with these bundles, particularly attachment molecules, are of interest in the field of dermatology, particularly in the study of skin which has been damaged from aging, injuries or the sun. Fibrillin microfibrils define the continuous elastic network of skin, and are present in dermis as microfibril bundles devoid of measurable elastin extending from the dermal-epithelial junction and as components of the thick elastic fibres present in the deep reticular dermis. Moreover, Marfan syndrome has been linked to mutations which interfere with multimerization of fibrillin monomers or other connective tissue elements.
Fibulin-1 is a modular glycoprotein with amino-terminal anaphlatoxin-like modules followed by nine epidermal growth factor (EGF)-like modules and, depending on alternative splicing, four possible carboxyl termini. Fibulin-2 is a novel extracellular matrix protein frequently found in close association with microfibrils containing either fibronectin or fibrillin. Thus, fibrillin, fibulin, and molecules related thereto are of interest, particularly for the use of preventing skin from being damaged from aging, injuries or the sun, or for restoring skin damaged from same. Moreover, these molecules are generally of interest in the study of connective tissue and attachment molecules and related mechanisms. Fibrillin, fibulin and related molecules are further described in Adams, et al., J. Mol. Biol., 272(2):226-36 (1997); Kielty and Shuttleworth, Microsc. Res. Tech., 38(4):413-27 (1997); and Child, J. Card. Surg. 12(2Supp.):131-5 (1997).
Currently, efforts are being undertaken by both industry and academia to identify new, native secreted and membrane-bound receptor proteins, particularly secreted proteins which have homology to fibulin and fibrillin. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound receptor proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)].
We herein describe the identification and characterization of novel polypeptides having homology to fibulin and fibrillin, designated herein as PRO334 polypeptides.
45. PRO346
The widespread occurrence of cancer has prompted the devotion of considerable resources and discovering new treatments of treatment. One particular method involves the creation of tumor or cancer specific monoclonal antibodies (mAbs) which are specific to tumor antigens. Such mAbs, which can distinguish between normal and cancerous cells are useful in the diagnosis, prognosis and treatment of the disease. Particular antigens are known to be associated with neoplastic diseases, such as colorectal and breast cancer. Since colon cancer is a widespread disease, early diagnosis and treatment is an important medical goal. Diagnosis and treatment of cancer can be implemented using monoclonal antibodies (mAbs) specific therefore having fluorescent, nuclear magnetic or radioactive tags. Radioactive genes, toxins and/or drug tagged mAbs can be used for treatment in situ with minimal patient description.
Carcinoembryonic antigen (CEA) is a glycoprotein found in human colon cancer and the digestive organs of a 2-6 month human embryos. CEA is a known human tumor marker and is widely used in the diagnosis of neoplastic diseases, such as colon cancer. For example, when the serum levels of CEA are elevated in a patient, a drop of CEA levels after surgery would indicate the tumor resection was successful. On the other hand, a subsequent rise in serum CEA levels after surgery would indicate that metastases of the original tumor may have formed or that new primary tumors may have appeared. CEA may also be a target for mAb, antisense nucleotides
46. PRO268
Protein disulfide isomerase is an enzymatic protein which is involved in the promotion of correct refolding of proteins through the establishment of correct disulfide bond formation. Protein disulfide isomerase was initially identified based upon its ability to catalyze the renaturation of reduced denatured RNAse (Goldberger et al., J. Biol. Chem. 239:1406-1410 (1964) and Epstein et al., Cold Spring Harbor Symp. Quant. Biol. 28:439-449 (1963)). Protein disulfide isomerase has been shown to be a resident enzyme of the endoplasmic reticulum which is retained in the endoplasmic reticulum via a -KDEL or -HDEL amino acid sequence at its C-terminus.
Given the importance of disulfide bond-forming enzymes and their potential uses in a number of different applications, for example in increasing the yield of correct refolding of recombinantly produced proteins, efforts are currently being undertaken by both industry and academia to identify new, native proteins having homology to protein disulfide isomerase. Many of these efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel protein disulfide isomerase homologs. We herein describe a novel polypeptide having homology to protein disulfide isomerase, designated herein as PRO268.
47. PRO330
Prolyl 4-hydroxylase is an enzyme which functions to post-translationally hydroxylate proline residues at the Y position of the amino acid sequence Gly-X-Y, which is a repeating three amino acid sequence found in both collagen and procollagen. Hydroxylation of proline residues at the Y position of the Gly-X-Y amino acid triplet to form 4-hydroxyproline residues at those positions is required before newly synthesized collagen polypeptide chains may fold into their proper three-dimensional triple-helical conformation. If hydroxylation does not occur, synthesized collagen polypeptides remain non-helical, are poorly secreted by cells and cannot assemble into stable functional collagen fibrils. Vuorio et al., Proc. Natl. Acad. Sci. USA 89:7467-7470 (1992). Prolyl 4-hydroxylase is comprised of at least two different polypeptide subunits, alpha and beta.
Efforts are being undertaken by both industry and academia to identify new, native secreted and membrane-bound receptor proteins. Many efforts are focused on the screening of mammalian recombinant DNA libraries to identify the coding sequences for novel secreted and membrane-bound receptor proteins. Examples of screening methods and techniques are described in the literature [see, for example, Klein et al., Proc. Natl. Acad. Sci., 93:7108-7113 (1996); U.S. Pat. No. 5,536,637)]. Based upon these efforts, Applicants have herein identified and describe a novel polypeptide having homology to the alpha subunit of prolyl 4-hydroxylase, designated herein as PRO330.
48. PRO339 and PRO310
Fringe is a protein which specifically blocks serrate-mediated activation of notch in the dorsal compartment of the Drosophila wing imaginal disc. Fleming, et al., Development, 124(15):2973-81 (1997). Therefore, fringe is of interest for both its role in development as well as its ability to regulate serrate, particularly serrate's signaling abilities. Also of interest are novel polypeptides which may have a role in development and/or the regulation of serrate-like molecules. Of particular interest are novel polypeptides having homology to fringe as identified and described herein, designated herein as PRO339 and PRO310 polypeptides.
49. PRO244
Lectins are a class of proteins comprising a region that binds carbohydrates specifically and non-covalently. Numerous lectins have been identified in higher animals, both membrane-bound and soluble, and have been implicated in a variety of cell-recognition phenomena and tumor metastasis.
Most lectins can be classified as either C-type (calcium-dependent) or S-type (thiol-dependent).
Lectins are thought to play a role in regulating cellular events that are initiated at the level of the plasma membrane. For example, plasma membrane associated molecules are involved in the activation of various subsets of lymphoid cells, e.g. T-lymphocytes, and it is known that cell surface molecules are responsible for activation of these cells and consequently their response during an immune reaction.
A particular group of cell adhesion molecules, selecting, belong in the superfamily of C-type lectins. This group includes L-selectin (peripheral lymph node homing receptor (pnHR), LEC-CAM-1, LAM-1, gp90MEL, gp100MEL, gp110MEL, MEL-14 antigen, Leu-8 antigen, TQ-1 antigen, DREG antigen), E-selectin (LEC-CAM-2, LECAM-2, ELAM-1), and P-selectin (LEC-CAM-3, LECAM-3, GMP-140, PADGEM). The structure of selectins consists of a C-type lectin (carbohydrate binding) domain, an epidermal growth factor-like (EGF-like) motif, and variable numbers of complement regulatory (CR) motifs. Selectins are associated with leukocyte adhesion, e.g. the attachment of neutrophils to venular endothelial cells adjacent to inflammation (E-selectin), or with the trafficking of lymphocytes from blood to secondary lymphoid organs, e.g. lymph nodes and Peyer's patches (L-selectin).
Another exemplary lectin is the cell-associated macrophage antigen, Mac-2 that is believed to be involved in cell adhesion and immune responses. Macrophages also express a lectin that recognizes Tn Ag, a human carcinoma-associated epitope.
Another C-type lectin is CD95 (Fas antigen/APO-1) that is an important mediator of immunologically relevant regulated or programmed cell death (apoptosis). “Apoptosis” is a non-necrotic cell death that takes place in metazoan animal cells following activation of an intrinsic cell suicide program. The cloning of Fas antigen is described in PCT publication WO 91/10448, and European patent application EP510691. The mature Fas molecule consists of 319 amino acids of which 157 are extracellular, 17 constitute the transmembrane domain, and 145 are intracellular. Increased levels of Fas expression at T cell surface have been associated with tumor cells and HIV-infected cells. Ligation of CD95 triggers apoptosis in the presence of interleukin-1 (IL-2).
C-type lectins also include receptors for oxidized low-density lipoprotein (LDL). This suggests a possible role in the pathogenesis of atherosclerosis.
We herein describe the identification and characterization of novel polypeptides having homology to C-type lectins, designated herein as PRO244 polypeptides.